Band is a thing from elementary school to college. So it's facially idiotic to the man on the street to call a single trumpet player "the artist".
The apparatus to deliver a major pop event is very visible, literally. And it's also obvious that the band didn't put up the stacks of speakers, run the mixing board, etc.
Whereas for a sculpture or painting, it just shows up. Voila! Often without any artist visibly involved. There's now a thing on the sidewalk, or in a museum or gallery.
There's probably a nice way to express this using the term "degrees of alienation", but I can't figure it out before I go back to work. :)
You're talking about making money, but no mention of making music.
A better argument is that art is getting more technical. or even just that's it's getting physically bigger.
Also, when music is commercial it's still called music.
Art stops being art when it's made for money. It becomes illustration, design, decoration or some such thing.
Historically a lot of EU or American artists are pretty much trust fund kids. because if you need to think about money all the time... you can't make art. Art requires some modicum of genuine freedom and most people need money to find it.
I'm not sure how that works for music.
And this is why "Art For Art's Sake" was invented when the middle class began to encroach on the upper class's ownership of art and the ability to make it. After all, if your social inferiors can do something, is it really special? No. So either abandon it, or define it to be something those people can't do after all.
I suspect most musicians also don't draw a bright line between artistic and commercial work.
Even the instrument that I play... it bears the name of a master, but there's no secret about the fact that it was produced in a workshop, as the fiddles "made" by Stradivarius probably were.