I think it seems to be a pet hate of anyone I have met who is producer and been doing it for a while.
Strangely people who are new to it immediately want to squash the hell out of everything because its the fashion... then after a year or so seem to learn that is sound a hell of alot better o get a good mix and apply a bit of gentle levelling and smoothing
My real pet hate is that most post production all-in-one-instant-mastering plugins seem very orientated toward this squash the hell out of it approach and so they sound like shit, and still seem to sound like shit when you try and be gentle with them.