I agree, and I think NotTooOld has nailed the reason why. It's something to do with guilt, I think. Parents seem to be under more pressure than ever to be seen as "perfect" despite, or perhaps because of, a lack of time. I think there have always been competitive "pushy" parents but the idea of "performance parenting" seems to be at fever pitch, and seems to be associated with the idea that, if a parent (usually mother) is short on time to spend with her then it follows that the available time has to be of "good quality" and not wasted on "meaningless" stuff like relaxing, playing with friends, or-heaven forfend-watching the telly.
I think the current media is brilliant at exploiting parental insecurity, and most parents fall for advertising pressure at some point. The problem, though, is that once these full-lifestyles become the norm -and by and large, very busy children are now the norm-any departure from that norm makes the comparatively laissez-faire parent appear lazy and perhaps even neglectful.