Are they right? I don't really listen to the radio that often, but I do admit that the last time I did, I thought along the same lines. There was a hell of a lot of EDM clogging up my speakers,I tells ya.
However, I'm not entirely sure if this is a new phenomenon. I distinctly remember periods in the past- when I did listen to the radio- that it seemed to be dominated by boy bands (Backstreet Boys/Take That/ Boyzone), then girl groups (Spice Girls/ All Saints/ Destiny's Child) and then rap music (Ja Rule, Eminem, Dr Dre). Heck, there were even times when our Divas appeared to be ruling the waves: first in the earlier 90's with Whitney/Mariah/Celine, and then again at the close of that decade with Britney/Christina/Pink.