> Absolute nonsense.
I think the point was poorly put. I suspect most musical experiences throughout history were either not paid for or paid for voluntarily, not as a condition of access. I also suspect that there is a strong tradition throughout history of professional musicians but that the majority of musicians then (and now) are not professional but amateur (in the positive sense of that word).
> Plato complained in his writings about popular musicians holding unruly concerts.
Did he talk about how they were paid? otherwise I fail to see the relevance.
> The invention of recorded music was a disaster for professional musicians, because it rendered most of them unemployed.
That is an interesting claim, I am prepared to believe it, but I would like to see evidence supporting it. I would suspect that the money to be made by playing music created by other people was reduced. I would also suspect that this stimulated the creation of new songs and musical styles since new copyrightable work became a much more important means of earning income from music.
> People of the past had far more limited access to music, but they weren't stupid or undiscerning - they wanted to hear the best possible music and were willing to pay for it. Busking is probably as old as currency and remains a perfectly reasonable way of making a living.
The modern innovation on busking is platforms like patreon. I pay a monthly amount to a musician I have spent innumerable hours listening to while working. I suspect that payments for access to live performances and voluntary support of musicians you like is the future of musical income. Musical copyright stimulates the creation of some types of music and suppresses other types. It also primarily benefits larger, older, entrenched entities at the expense of suppressing newer, smaller and more innovative entities.