I fall between the extremes here, for several reasons. First, I think "pop" music was always cotton candy to some degree (though there was material I liked and still pull out occasionally). The major labels were dragged into the "youth explosion" (say, post-Monterey Pop Festival) only because there was money there and a big market to be satisfied. A few savvy A & R people got it, but apart from The Beatles, which were kind of sui generis and acts that followed the British Invasion template -Sir Douglas Quintet anyone?- much of what was released in coming years followed trends. Psych- yeah, that lasted a couple years- not enough there to hold the mainstream (much as I love it). Prog- died pretty fast, wasn’t radio friendly, and the formalistic faux classical stuff just didn’t work for a lot of people (e.g., I dug ELP’s first album, but Pictures left me cold- I only revisited it in the last year or so, largely due to Greg Lake’s wonderful voice and acoustic playing).
The Band got some radio play, but were regarded at the time as under appreciated. (Their work didn’t really lead to a wholesale discovery of "roots/Americana" until the last few years). Disco and punk--some fun stuff, but kind of limited.
The ’80s had a sound all its own, much of it dated today. Then "grunge" with Nirvana, and a lot of follow on acts, some of which were pretty good.
Lurking on the sidelines, below the top 40, was the stuff people "discovered" for themselves, by word of mouth, through reviews, etc.
I think there’s good stuff out there today, but it may be harder than ever to sort through it-- very little money to promote coming from record companies and the splintering of so many different sub-genres that people follow through the Internet, much of it free. The flip side is that the Internet can give you access to a huge pool of talent if you are willing to do some digging.
Consider whether you were an adventurous listener at the age of 13-16, or whether you wound up listening to a lot of what your friends were into.
Some of the urban/hip-hop isn’t bad, though there are only a handful of those acts that I find musically interesting. Just like the ’80s sound, today’s "neo-soul" follows a template. Very little of it is innovative or engaging. But, I think the same could be said for almost any decade of popular music. You have to dig deeper to find joy.
FWIW, and this may be heresy, but I never really "got" Sgt. Pepper’s at the time of release and still don’t play it that often; when I do, it is a few discrete tracks rather than the whole album. Granted, it has been hyped as the best album ever made if you believe in such stuff, but my musical interests are diverse enough, as is my willingness to explore beyond the boundaries of convention, to find satisfaction in a variety of music, old and new.
+1 to @kennovak for throwing down some newer acts even if not all of them are appealing to me.