I know that OP wasn't even born yet when "Rumbleweight" was a thing but, yeah. Rumble looks like he's hanging around his typical walkaround weight when not cut down to a proper fighting weight, or emaciated for a weigh-in at a class he has no business trying for.
GSP doesn't look much different from out-of-camp (notice no extreme fat layer), but his gut looks bloated from the inside. Could be that he had an intestinal issue (he did, IIRC), or could be just caught the photo at the top of a deep breath. He's always had a "HGH gut" looking belly, even on the scales.
Hendricks and Hendo both look like their walkaround-weight selves. Hendo maaaayyybe just little more around the waist, but he's not considerably fatter.
Mir/DC: Again, I don't think you understand the definition of the word "retired".