On top of that, music was not a commodity back then. Live performances literally made a living for many of them as these performances were the only source of music. (And a church needs this music for every mass, for instance.)
Now music is abundant, recordings are cheap / free, and the best performance is easily available in a recorded form. Live performances are still a thing and still feed many of the music creators. Royalties, too. But you better be a superstar for that to bring enough. (Liszt and Mozart were superstars, in a sense.)
Wait until a Dall-E equivalent for music emerges though.