When I was little I always though that being famous was a merit thing. If a musician was known it was because he or she was excepcional in his/her art: an incredible singer, a highly skilled guitarist, an amazing drummer.
But then I got older and saw a lot of gigs, and a lot of disciplined and truly amazing musicians that nobody heard about… And most were struggling financially, having a side job just to get by. How come? What is missing from them that the “icons” have?
To add all the other good comments here…
As a recording artist, it’s nearly impossible to stand out unless you have a marketing machine behind you. That means a record label that can promote your work, get your songs placed on radio stations and streaming platforms, and (in the old days) manufacture and sell physical media through many different retailers.
As a touring performer, you also need a large crew of people working for you: booking venues, marketing your shows, ticketing, managing the logistics of set-up/tear-down/transportation, operating lights and sound during the show, etc.
In both of these scenarios, the musician is only one small cog in a large machine. And there are enough good musicians in the world that they are treated as largely interchangeable.