More than clipping it bothers me that metal parts stretch with animations. It looks so completely off..like fake armor.
This is one of my pet hates with video games in general. Speaking as an admittedly rather novice modeller it seems to me like a tricky problem to sort out and I suspect it might make the potential for clipping and deformation problems 10× worse, so stretchy metal might be the least worst approach. :| I guess there's a reason chainmail is so popular! Though I've still seen plenty of examples of even that getting pretty conspicuously stretched.
Weighted stuff like cloaks and so on seem to be another frequent problem I've seen in lots of places and I still seem to have traumatic memories of trying to rig e.g. skirts in Fallout 4. D: I suspect it'll be a perennial problem until game engines can do a sort of proper mesh collision detection system without crippling performance... Hmm, that sounded much more defeatist than I'd intended; I should probably stop prattling.