This turns into a generational war easily. Like we need any excuse for that.
But I make an absolute distinction between pop of different periods, and the definition of pop. In the 50's and early 60's, the producers dictated the sounds of their studios, and manufactured artists (by discovering and cultivating talent) to fit with that product vision. In the 80's through today, the producers still dictate a lot of what gets recorded and how. The late 60's and 70's, however, was an open window in "music for young people", where groups could explore very wide concepts. Some of them worked and some didn't, but there was a lot of freedom to explore in the studio. Perhaps some baby boomers miss that. I know I do.
Before unloading on me, there have always been those who found ways to put their unique vision out there. But I'm not talking about that, I'm talking about how experimental groups could be with mainstream record-company money and support.
I suspect lots of the oldest boomers like the pop music of the late 50's and early 60's just fine, and it was as cheesy and formulaic as anything produced now. The OP's summary of complaints applies to much of that just as much as it does to current pop.
Of course, we tend to hear the best of the past, because only the music that stood the test of time still gets played.
Do we use the term "pop" to describe some of that 70's stuff that did not conform to those generalizations? I'm thinking of groups like Yes, King Crimson, Jethro Tull, Genesis (particularly when Peter Gabriel fronted the group), ELP, the Moody Blues, and many others of that ilk. However bombastic and self-indulgent that genre was at times, it was not formulaic, and was filled with complex rhythms, tonalities, variations, true improvisation, experimentation bordering on the avant garde, and dynamic contrast. But the Yes of 1970 (and particularly in the 7 or 8 years that followed) wasn't "pop" in the sense that, say, Bobby Sherman was pop. Even Elton John of 1970 was not pop in the sense that the Monkees were, though that's much less obvious. Was David Bowie or Emerson, Lake and Palmer pop in the sense that the 5th Dimension, or even the Jackson Five, was? Of course, some of those pop stars broke out of mere pop and made the genre something more special because of it, but those (e.g. Michael Jackson) were the exception, it seems to me. Yet that prog-rock (as we call it now) stuff was right at the center of rock music adored by baby-boomer musicians.
As I said, there are groups doing that sort of thing now, and some of it is remarkable. But those aren't the groups you'll see or that will be represented on American Idol.
Rick "get off my lawn!" Denney