Geee parent
It's not sampling. Sampling is copying & pasting, but that doesn't happen, technically. Just like stable diffusion doesn't copy any artworks. AI learns from previous works, but doesn't copy them. It's quite similar to how humans learn and make adaptations based on other work.
While technically true, the unspoken premise of my argument is that it can and will output distinctive samples derived from the source. E.g. you cant change the pitch, tempo, and add other effects and call the output your own, legally.
Its a landmine
Do you mean it's a minefield* :P
Not sure it's as much of a problem as you're making it seem though.. likely there can be enough iteration that it would not be distinguishable.
Also lots of mainstream artists ignore copyright anyway (Kanye West etc). Plus you could just use training data that is from public domain stuff if it was really such an issue, there is decades worth of music that are outside of copyright law.