Oh, for sure. The trend started in the mid-to-late 70s. But it wasn’t overwhelmingly dominant like it was in the 80s.
Anyway, there definitely were a lot of genres created/popularized in the 80s, but my problem is that they became stratified. Alt rock didn’t influence rap, metal didn’t influence synthpop, etc. The thing I love about the 60s is that rock cross-pollinated with many other forms of music, rather than stratifying into ever-more-specific subgenres. You get jazz rock from Chicago Transit Authority and Blood, Sweat, and Tears, and at the same time, you get Frank Sinatra putting out soul-influenced music to try to appeal to a similar crowd. The Rolling Stones would occasionally branching out from their usual fare to make a medieval song like Lady Jane, or a samba like Sympathy for the Devil. The Mamas and the Papas covered everyone from the Beatles to Rodgers and Hart to the Temptations, putting their own original spin on famous songs. Creedence Clearwater Revival combined country and folk with hard rock. The Byrds combined folk with psychedelic rock. And of course the Beatles combined basically everything. Even though there were a lot of distinct genres popular, they weren’t isolated from each other or from the music of the past. It even goes down to the level of instrumentation: you could get a flute solo in a hard rock song like Wild Thing, or a hurdy-gurdy in a hard-rock-tinged song by folk-rocker Donovan. There were fewer creative boundaries for popular music in the 60s.
Now, I’m not saying genre stratification is all bad; if it’s limited cross-pollination, it’s expanded the limits of what rock can be. (And of course, in the 80s, there was some of that cross-pollination I illustrated, but it wasn’t as common.) But, and this is kind of the crucial point for me, most of the real creativity in the 80s went on “underground.” In the 60s (and most of the 70s), the most creative groups were often the most popular ones. Who was the most popular musician of the 80s? Probably Michael Jackson. I’m not here to say his music is bad, but is it, and the similar stuff that was also very popular in the 80s, anywhere near as creative as what was dominant in the 60s? Not remotely.
In conclusion, I guess my point isn’t necessarily that the 60s were “more creative” than any other period when you look at the full spectrum of music being produced, but when you focus on what was really successful, they were a high point. I’m not going to tell you your taste is bad or something–I like a lot of the stuff you mentioned, and I’d say the 80s are probably my 3rd favorite decade for rock overall. But, personally, my personal preference is for the wonderfully ill-defined mess of the 60s, rather than the well-defined genres and subgenres of the 80s.
Hopefully that came across as a coherent response and not the ravings of a madman. XD
Edit: another big factor for me is that 60s hits have a lot more emphasis on genuine emotion, whereas 80s hits are more focused on being catchy and “danceable.” But I think this comes down to a fundamental difference in how we look at the music of the past–when judging an era, I focus more on what was popular; you focus more on the totality of musical expression.