Further, I would put the hypothesis into the room that the revenue mix has also shifted. From selling music to selling tickets, merch, etc.
Any ideas on those two things?
For example if you're Marc Rebillet you improv everything, Marc has a loop sampler, a couple of laptops, a keyboard synth, headphones and and a microphone, he makes noises, or sings, and the loop sampler creates rhythm because that's how loops work - so he's "just" on the fly coming up with the words and the tune. Maybe Marc spends 10 minutes going from silence to a backing track and then puts together a 5 minute song about, I dunno, how amazing squirrels are, "Tree Rat God Freak". Seems to me that's 15 minutes and if a thousand people stream it and Marc gets paid $4 for that it's a profitable use of his 15 minutes.
[ Of course because watching this happen live is fascinating people actually pay to watch Marc on Twitch, so he gets more than $4 before the song is even finished ]
On the other hand, maybe you spend six months composing an orchestral piece, you need a full orchestra to perform it, that takes them several hours to rehearse and get it down, and then a million streams of that doesn't really pay everybody for their time.
Anyway, the real question is how the net income compares to living expenses, and how that had developed over time.