> Yes, but the vast majority of musicians do have formal coaching and training.

I really doubt the majority of musicians trained at a conservatory or similar institution exist is what the person you’re responding to said. Having gotten some amount of lessons at some point is not the same as spending even three months at a conservatory.

> A net worth is not an indication of musical talent and should not be used as one.

But it is an indication of how much the public values your work, a very noisy one, to be sure, but by far the most democratic measure if that’s something you care about.

True, but musical talent doesn't mean I should give you anything. If you ask something of me (money? time?) I may demand something in response (entertainment). Should we fail to make a deal, you are out the money/time and I am out the entertainment and we both seek out others who may be agreeable. This is fair. This is free. This is the market. And it is today.

This article is about P(good life|college degree)

Global popularity and net worth is not everything, but you could say that is "a good life", in the context of this discussion.

If we restrict this only to artists, a degree doesn't guarantee a base level of popularity or base income.

This could be explained by selection bias more than teaching success.