Technology

That's covered by section 107 of the US copyright law, and is actually fine and protected as free use in most cases. As long as the work is a direct copy and instead changes the result to be something different.

All parody type music is protected in this way, whether it's new lyrics to a song, or even something less "creative" like performing the lyrics of song A to the melody and style of song B.

Taking other people's creative works to create your own for-profit product is illegal in every way except when AI does it.

No, actually its completely legal to consume content that was uploaded to the internet and then use it as inspiration to create your own works.

Taking other people’s creative works to create your own productive work is allowed if you are making a fair use. There’s a very good argument that use such as training a model on a work would be a fair use under the current test; being a transformative use, that replicates practically no actual part of the original piece in the finished work, that (arguably) does not serve as a replacement for that specific piece in the market.

Fair use is the cornerstone of remix art, of fan art, of huge swathes of musical genres. What we are witnessing is the birth of a new technique based on remixing and unfortunately this time around people are convinced that fighting on the side of big copyright is somehow the good thing for artists.

Thousands of hours of work on a project you completed being used by someone else to turn a profit, maybe even used in some way you vehemently disagree with, without giving you a dime is

exactly how human culture progresses, and trying to stop it

is unethical and needs regulation from that perspective.

Taking other people’s creative works to create your own for-profit product is illegal in every way except when AI does it.

wrong.