A fairly vocal portion of lemmy is AI-hostile, and even for the people who aren't outright hostile to it, it can be annoying at times -- AI content does tend to drown everything else out when it's permitted, so making a community explicitly for it would probably work better.
lemmy.dbzer0.com might be a good place to host a community specifically for exploring AI generated music if you're interested in running one. That instance is explicitly open to AI gen and already has several image gen communities, but I don't think they have a music gen community yet. (Double check though before making one in case I just missed it.)