Pop-ular Music Trends?

For the purposes of this thread, I am talking about big-company radio station type music. Not necessarily just pop-music as the modern genre since a lot of today's music also includes things like dubstep, dance, techno, R&B, soul, etc. But if you hear or heard it on a "music of today" type radio station, then that's what I am talking about. Essentially the classic definition of pop-music, not just the more limited modern "pop" genre.

Having defined the scope, my question is if this pop-ular music has plateaued, or maybe reached a local peak.

I realize as everyone ages, the newer music become more and more crap while the tunes you grew up with become better and better. However, bear with me.

BBC Radio 1 does this thing called the "10 minute takeover" everyday. 3 songs get played, no matter what the age or genre. If it is in the system, it gets played. Over the past years I've been listening, almost every one of these songs has been a mid 80's to late 90's song. So when the people get to choose, they choose a 20 year period that doesn't include much from this millennium. The last time I listened to local terrestrial radio it was when people still called in to ask for their favourite music to be played and dedicated to someone. I remember the transition on the same stations from when everyone requested the modern music to when everyone started requesting the hits of a couple years ago, and then many years ago, all within the same period. Now almost a decade later, the requests still come from the same time period.

I listen to lots of the modern stuff and find most of it quite enjoyable. However, I find a much smaller percentage of proper tunes. The songs that if you hear them on the radio as you are pulling into your destination you will sit there listening to the end of the song instead of just shutting it off. Something that if your MP3 Player got stuck on a loop, you'd be OK with that for at least a little bit.

I don't consider myself that ancient although I am constantly reminded of my aging by all the tiny babies I knew that are now entering highschool.

My other hypothesis has been for a long time that people long for the music of eras past because they only remember the hits, so of course every song is awesome, they are already proven. Whereas today, there are hits in there mixed in with all the crap. I have held this belief for a long time, but I am starting to question the validity of the hypothesis because there is a good 10 year gap of requested hits. I would have expected for a distribution, rather than a cliff.

Just curious if anyone has experienced something similar. If your audio source of choice has a similar request system, have you noticed any sort of trend?