It’s not weird, it’s just lazy. The Simpsons is cropped because that’s what Fox did for the HD version, and they’re too lazy to use anything else. Splash covers up the nudity because that’s the censored for TV version, and they just thought they might as well go with that.
As the occasional sight gag has been obliterated by the cropping, I can only presume it was supervised by Mr. Magoo.
Uncropped Simpsons reruns are still airing on a local L.A. station.