Music is mathematics.
Anything based on mathematics of discrete values can be computed.
AI could, in theory, compute all possible values of arrangements of those discrete units (notes and their timing).
Of the “songs” created, some will be pleasing, most will probably be displeasing, and still others will be the computed duplicate of music already created.
Probably don’t even need AI, just a really good background in music theory and requisite skill with a chosen programming language. AI will just make it easier for the … less skilled, to be able to implement “copyright” monopoly and copyright litigation farming.
Though, if AI were creating movies, maybe it could be taught to NOT create so many duplicate, derivative, boring and bland “rewrites” or “reimagining” of past works that do nothing more than change the sex, gender or skin color of the characters.