"Power pop" is entrenched as an adjective but I don't know if it's ever functioned as a genre, e.g., there being power pop stations and power pop magazines and power pop bands, or "Let's go out and hear some power pop." Maybe there are, or were, and I just didn't know about it. I could say "The Bangles are power pop" and "The Go-Gos are power pop" or "The Knack are power pop" but that's not really how those bands got classified generically. Rather they were "pop punk" or "new wave," even though it made sense to call them power pop, too.