The answer is that no one is trash, while many people, if not most people, are lost.
In the Biblical times, and in the time of the giving of the Qur'an, understand that God's word was being preached and given by God to the prophets to people who were, like most people of the world then, very poor. Many starved if there was just one missed harvest in a year. People lived "hand to mouth," as the old saying goes (in other words, what they gathered for food went straight into keeping them alive day to day). So people had no concept of "garbage." Nothing went to waste and there was no such thing as "trash" in the first place. Thus God would never use such a term to describe even the worst of the worst of people since the people he was speaking to would not understand the concept of "trash" or "garbage" at all. Remember people even went "to the bathroom" in agricultural fields and pastures so that it could compost and enrich the soil (not a problem when there were many fewer people than today; today we need sanitation systems both for cleanliness and the environment).
So my first point is that God speaks to people using terminology that is 1) perfectly accurate, as God is perfection and thus is truth personified and 2) is understandable and relevant to the people who lived at the time AND remains truthful and understandable through the ages.
Thus when God chides people, notice that he never refers to them as trash or garbage while they are alive. From this you need to understand that thinking of any person as "trash" or "garbage" is against God's example and teachings. No one, no matter what they say or do, is trash or garbage. What are they, then? They are "lost."
Someone who is lost is someone who does not know where they are. "Lost" does not mean, in scripture, losing a game. Remember, the Bible is not full of modern double speak, double entendres or "coded" messages, or modern slang. Lost means lost. Someone who is lost is someone who does not know where they are.
Matthew 10:5-7
These twelve Jesus sent forth, and commanded them, saying, "Go not into the way of the Gentiles, and into any city of the Samaritans enter ye not. But go rather to the lost sheep of the house of Israel. And as ye go, preach, saying, The kingdom of heaven is at hand."
Here Jesus is ordering the disciples to seek out those who are lost...not trying to convert others from their beliefs, but to find those who are lost. And the lost at the time of Jesus were the Jews. No one is "trash" or "garbage," they are lost.
Matthew 18:10-14
Take heed that ye despise not one of these little ones: for I say unto you, That is heaven their angels do always behold the face of my Father which is in heaven. For the Son of man is come to save that which is lost. How think ye? If a man have a hundred sheep, and one of them be gone astray, doth he not leave the ninety and nine, and goeth into the moutains, and seeketh that which is gone astray? And if so be that he find it, verily I say unto you, he rejoiceth more of that sheep than of the ninety and nine which went not astray. Even so it is not the will of your Father which is in heaven, that one of these little ones should perish.
Many recognize this as one of Jesus' most crucial passages for all the obvious reasons, but they miss the point that was being made obvious in the cultural context of the times, and which has now come full circle again in modern times. The closest Jews had to "trashy" people were the children. The disciples tried to shoo the children away from Jesus (and not in a cute way) because children were thought to be somewhat valueless when it comes to any matter of importance, such as salvation. So this is the closest that one can find in the Gospels where there is a superior attitude by class (adults over children) and Jesus immediately stomps on that with no uncertainty. He will not allow the disciples to even for a moment view children as kind of bits of trash hanging about. Jesus tells them that the opposite is true: that the children's guardian angels constantly face God himself in heaven.
Then Jesus slides directly into discussing, again, how they are to seek the lost. Children are lost because they have not yet received the word of God. This is why Jesus slides immediately from chastising the disciples for downgrading the dignity of goodness and being of children to telling them how both children and adults must be viewed, as lost sheep. Notice Jesus does not say, "Well, unless of course the lost sheep is kind of a trashy one and then it's OK for it to be lost because it does no good anyway."
Before discussing scriptural admonitions to view people as "lost" and not "trash" or "garbage" any further, let me point out where the "trash" does indeed get "taken out" for disposal. That is at the end of life when each person is judged, and at the End of Times. What is "trash" is the sum total of a sinful life after it has been completed in the living. Until a person dies and is judged they are not viewed as "trash."
What was Biblical trash? The dry husks, the hull, of wheat, which is called chaff.
Psalm 1:4
The ungodly are not so: but are like the chaff which the wind driveth away.
Jer 23:26-32
How long shall this be in the heart of the prophets that prophesy lies? Yea, they are prophets in the deceit of their own heart; Which think to cause my people to forget my name by their dreams which they tell every man to his neighbor, as their fathers have forgotten my name for Baal. The prophet that hath a dream, let him tell a dream; and he that hath my word, let him speak my word faithfully. What is chaff to the wheat? saith the Lord. Is not my word like a fire? saith the Lord; and like a hammer that breaketh the rock in pieces? Therefore behold, I am against the prophets, saith the Lord, that steal my words every one from his neighbor. Behold, I am against the prophets, saith the Lord, that use their tongues, and say, He saith. Behold, I am against them that prophesy false dreams, saith the Lord, and do tell them, and cause my people to err by their lies, and by their lightness; yet I sent them not, nor commanded them; therefore they shall not profit this people at all, saith the Lord.
Both of these passages underscore that genuine "trash" is symbolized as ungodliness and false prophecy. It is the sinful actions, not the human integrity, that is being condemned by God as chaff, which is wispy trash that is either blown away into the wind, or burned in the fire. God is saying, in his very own words, that the words of the prophets who spread lies via their own dreams and other gossipy falsehoods are "light" as in "lightweight" and thus like chaff will be easily dispersed and come to nothing at all in the end, while God's words are heavy, so heavy as to be like a hammer that breaks a rock into pieces. So this gives you understanding of the only context in scripture where something is viewed as "trashy," which are deeds, not the essence of the person. Thus this all leads to the role of Jesus Christ.
Matthew 3:11-12
[Spoken by John the Baptist].
I indeed baptize you with water unto repentance: but he that cometh after me is mightier than I, whose shoes I am not worthy to bear: he shall baptize you with the Holy Ghost, and with fire: Whose fan is in his hand, and he will thoroughly purge his floor, and gather his wheat into the garner; but he will burn up the chaff with unquenchable fire.
John the Baptist prophesies that the Christ, Jesus, will use the fire of the Holy Spirit to purge and retain the good, those who will enter the Kingdom of Heaven, and also use the fire to cast into the flames of hell those who do not repent, and that, again, is the image of the chaff being burned as symbolizing people who have misspent their entire individual life and thus are to the eternal fire condemned.
Thus one is to understand two things: 1) only God, and through Jesus Christ to whom this authority is given, will people be judged as "trash" as in chaff and 2) while their deeds in life may be sinful chaff, such as false prophecy, they are not to be given up on until the very end, when they have perished and receive judgment.
Luke 15:7-11
I say unto you, That likewise joy shall be in heaven over one sinner that repenteth more than over ninety nine just persons which need no repentance. Either what woman having ten pieces of silver, if she lose one piece, doth not light a candle, and sweep over the house, and seek diligently till she find it? And when she hath found it, she calleth her friends and her neighbors together, saying Rejoice with me; for I have found the piece which I had lost. Likewise, I say unto you, There is joy in the presence of the angels of God over one sinner that repenteth.
True godliness and being just, whether Jewish, Muslim or Christian, means that one never gives up on the lost sheep or the lost coin, knowing that God's mercy exists throughout a person's life. Thus one should never think of a human being as being "garbage" or "trash." However, one must also recognize that certain deeds are like the chaff, either of no significance to be blown away, or leading one to the fire, and that one must focus on the constant opportunity to repent and stop making one's self eligible to be treated as chaff by God at judgment.
I have to underscore something I alluded to earlier, about one's attitude toward children. Children were viewed as a bit like trash by the disciples only because they did not have the seriousness attached to them yet that comes with age and hence respect. But what do people today view children as? Look at the proliferation of child pornography and, hand in glove along with it, the crass way that young children are sexualized by adults, including their parents. Children were looked down upon by the disciples only because they were viewed as not being appropriately aged to partake in serious matters such as faith (listening to Jesus, for example), even though they were all being raised as devout Jews. Can you see how much more the horror of these times where children are actually treated and expected to treat each other as sexualized trash? Do you think anyone who promotes children as sexualized trash is going to escape the fire? Only if they genuinely repent, which is why the "lost" are the object of God's care and concern.
Notice that Jesus asked God to forgive those who crucified him because they did not know what they are doing (a sign of being lost). He did not point out which people are "garbage" or "trash" after all!
Revelation 14:16
And he that sat on the cloud thrust in his sickle on the earth; and the earth was reaped.
Wheat was harvested by a long sickle, and so this image of the wheat again enters at the end of times, when the whole earth is reaped for separating into chaff and grain. Again, what one must understand in the context of the entire bible is not that one is "safe" until the end of times, duh, but that discerning a person as "trash" aka chaff only takes place at the end of their life. People must and should refrain from categorizing anyone as being "garbage" or "trash" as 1) God himself does not do that 2) his genuine prophets do not do that 3) only certain ungodly deeds and pagan practices are actually viewed as chaff, not the people who do them and 4) God only deems people to be chaff and to be burned when they die, either at the end of their life or when all lose their lives at the end of times.
I hope that you have found this helpful.