It does seem the big thing with this round of consoles but was almost unheard of with the 360 & PS3.
It was certainly a 'thing' as there were many games running at sub-HD resolutions.
But there was an underlying expectation that the new consoles would be outputting 1080p as a minimum, and with the increased prevalence of platform comparison the resolution is arguably the biggest difference between the consoles so this is probably why you are hearing about it more now.