No, but it was scaled down plenty by several bands who did well borrowing elements from it while still maintaining some more mainstream appeal. Boston, Styx, Kansas (sorry, Dave, I still love your stuff) and several others. Even David Bowie managed to pick the carcass of prog while maintaining his own popularity. There was a lot on that carcass to pick, and I'd argue that the entire New Wave movement that came afterward owed a huge debt to the early progressive artists.
If anything, my belief is that progressive rock was absorbed by mainstream music more than anything else. Much of what was pioneered by progressive artists was later used by the hit-making machine, in some cases by those artists themselves. I'm looking at Peter Gabriel and Phil Collins here, for starters.