Only those in Christ. And we say all will accept Christ, either in this world or the next. Every knee shall bow.
Not so. The sinners are defined by their sins at the GWTJ. See Rev 21:8:
"But for the cowardly and unbelieving and abominable and murderers and immoral persons and sorcerers and idolaters and all liars, their part will be in the lake that burns with fire and brimstone, which is the second death."
The word 'death' is used in various ways in the Bible and Rev in particular. Can signify physically dead, or dead in Christ, or dead to Christ.
The aim of the second death is to kill death generally. Which means to give life. If death is killed, only life remains (by elimination!). So the lake of fire kills death and sin (that causes death).
That's why we see the nations who get zapped in Rev 20:9 or presumably chucked in the LoF as unbelievers in Rev 20:15 emerge repentant and worshipful in Rev 21:24-26, and get healing by the tree of life in Rev 22:2. It's because the judgment is they need a good cleaning up.
What a shame brother, you know the earthly truth, but you think God gives up on His creation? That's what the cross is all about - it's God guaranteeing us He'll go further to save than the devil can go to destroy. His love doesn't quit just because we do. What a petty deity that would be lol.
As all things came from God, so too shall all things return to Him.