AI is not very good at music yet, it can do things like decent imitations of composers like Bach who have a massive catalog for it to work off of and wrote under a fairly rigid theory but that is about it. Pop music is largely emotion based and does many nonsensical things (from a theory standpoint) based on emotion, AI is not good with that. The more rigorous types of music are far too fuzzy, every "rule" has an infinite number of exceptions which AI is not very good with either.
Played with riffusion some, not at all impressed by it. It is mimicking without understanding and while it occasionally did something interesting it has no real comprehension of time scales over short loops, no understanding of larger structures and fails completely on the prompt if it is something it can not easily research. This is about where AI generated music has been for a decade now and can not seem to push past. Part of this is probably because AI was integrated into composition a good long while ago, composers tend to treat it more like an instrument or a filter than something which writes music and most of the work with AI in music is towards those ends, not towards getting AI good at composition.