CHR/Pop hasn't been a mass-appeal format since the early nineties, as numerous articles in BB & R&R have pointed out over the past fifteen years.
Once the nation's adults & baby-boomers started bailing out of the CHR/Pop format in the late eighties, a trend started by KIIS's overreaction to KPWR here in LA in 1987, and which was copied in market after market throughout the nineties and continues today, CHR/Pop narrowed its target demo substantially, and the results suprised nobody.
The arrival of 'Smooth Jazz' pioneer KTWV in LA in 1987, combined with the explosion of country radio (with Garth Brooks) in 1989, led to the abandonment of the format en masse, as millions of soccer moms bailed out of the format, horrified by the presence of vulgar music which they couldn't tolerate, and sure as hell didn't want their VERY impressionable kids to hear.
Today's Hot AC (or Adult Top 40 or Adult/CHR) format has by default become the mass-appeal format what CHR/Pop used to be, and that is certainly the case today, although the format continues to be plagued by an overreliance on research and very tiny libraries.
You shouldn't be surprised that Clear Channel's CHR/Pop stations lean rhythmic, as does the format itself; just look at the top 30/40 songs on both charts, and you'll see for yourself.