Not rich, but the best way I’ve seen to make a living or at least some decent side money is … .selling stuff/services to the people who want to get rich. I’ve known several independent guitar store owners, as well as video/photographers, teachers and so on. Almost all of them made far more money than the actual musicians I knew. I personally know ONE guy my age (early 40’s) with decent success, and he still does carpentry projects to pay the bills. The only other guy I know who has made money was in a decently popular 60’s band and is something of a local legend in the Tacoma area, I’d bet he’s comfortable at best from past royalties and current gigs. That’s two guys out of hundreds I’ve met. I’d bet somewhere around 99% of musicians lose money if you count gear/lessons/actual school/gas and so on trying to make it.