There may be an element of that in it. But remember that mass commercialization has always been done in music. The name that immediately comes to mind is The Monkees.
But new and good music always shoots up between the cracks if it exists. But as far as I can see, it just ain’t there any more.
Oh, there are tremendous musicians out there - they have just forsaken the corruption-riddled record company/radio distribution channels and are finding ways to sell their product directly through the Internet. I don't think the situation for young musicians is hopeless, it's just that the traditional path of playing in a bar and getting discovered by record company A&R men is no longer viable.
There's more good music out now than has ever existed. Most of it won't be played on the radio, though, so one has to search for it.
The Monkees was a teevee show about a band. The Coasters and especially the Drifters were about commercialized vehicles for the songs of Lieber and Stoller. Ever changing casts, I mean bandmembers, several Drifters on tour at the same time during the original "incarnation" of the band.
Mowtown was studio musicians and put together bands/song-writer productions as well. But everyone has to pick on the fictional Monkees.