Interesting insight and I agree.
I wonder if the issue could be that the AC format can't survive without the upper end of 25-54, which probably likes 70s and 80s music? When B-101 in Philadelphia dropped the 70s, WOGL started increasing and has surged to #1, while WBEB/B-101 fell back. AC stations also tend, in a lot of markets, to do better when there isn't a Classic Hits station. AC stations have become so gold obsessed/focused, that "new" music has become an afterthought. Despite them being in the top 15, Premium Choice AC still isn't playing Fun. / Janelle Monae, Norah Jones, One Direction, Carly Rae Jepsen, Katy Perry (Wide Awake), or Jason Mraz. All fit the format well.
I don't understand any other reason why AC stations now have to hold on so to 70s/80s music and burned-out recurrents instead of embracing more NEW music. The top 15 on AC right now is fantastic and has a lot of variety, better than the format has had in years, from "Call Me Maybe" to "Happy Pills" to "Wide Awake" to "We Are Young." They should take advantage of it.
This is what I'm noticing - more and more females in their upper 30s and early 40s are listening to CHR (in addition to Hot AC) along with their kids and liking it. This wasn't really the case in 2000. CHR is probably the most "soccer mom friendly" right now that it has ever been. That audience is sticking to CHR/Hot AC longer instead of moving in to AC like we've seen in recent times. When they want to hear something old, they may go to Adult Hits or Classic Hits where it isn't as boring or repetitive. That poses a problem for the "Best Variety Of Yesterday and Today"/Delilah/Shania Twain, Rod Stewart, Elton John, and Daughtry AC's. Do they continue to emphasize 70s and 80s to maintain their (aging) audience, or start playing more currents off of the AC chart and embracing new music? Smaller markets are doing the former, larger markets are doing the latter.
IMO, AC has become a 35-54 format with a bias towards the upper half of that. It seems to me that as AC has gotten harder and harder in sound, there is less to distinguish it from other formats. 70s and 80s are on Classic Hits and Adult Hits, those decades plus 90s are on Adult Hits, and 00s/much more current are on Hot AC/CHR. Where does this leave the AC? I think that in the near future, these AC's are going to have to decide if they want to come in to the 2010s or be classic hits stations.