I always listen to my wife, thirty years experience has shown me her wisdom. The "young things" have little to say-Fox News with their "info babes" is particularily guilty of the pretty face fallacy.
I've noticed the same thing - I thought it was a job requirement or something that they had to have fast shrill teeny-bopper voices to be a newsreader, but maybe it's the technology like you say.
Either way, I cringe when they talk.