As far as planting his back foot from shotgun or a straight dropback, striding into the throw and taking a hit, it almost never happens. Just as Brett Favre fell into poor throwing mechanics later on during the Mike Sherman years, Rodgers is following suit.

You see a lot of all-arm throws, skipping into throws, firing off balance and across his body. He sails one pass, bounces another. At times, his feet don’t work in unison with his torso. His deep-ball accuracy, once extraordinary, has improved somewhat from a year ago when it was embarrassingly bad for a player of his stature.
It's shocking to me how his mechanics have declined. It used to be what set him apart from the merely good quarterbacks. Is McCarthy not stressing mechanics as he once did, or is Rodgers uncoachable? McCarthy recently got upset in his PC about the perceived negativity others see in his offense. My guess is he knows Rodgers is the main problem, but doesn't want to publicly say it. Favre went through a period like this in 1999-2000, and was able to largely reverse the decline. Rodgers could do it too, but it starts with acknowledging the problem exists.