211 isn't very heavy guys. I think perhaps in the 70s guys had comparitively little weight in their legs so they had massive upper bodies, and especially chest and arms, but still didn't weigh mega poundages because their legs weighed fuck all. Kai is someone who carries a higher percentage of his weight in his legs than most, even back then.
The same reasoning applies to Gunther, he has some serious bulk in his quads and back and waist, but doesn't look 60lb heavier than arnold in any pose where arms and chest are emphasised, because that's not where he's carrying most of his weight. Hence the progress of bodybuilding to more overall development has created less aesthetic, less "wow factor" competitors, arguably. The 90s seems to be when the balance was best. Now days guys weigh 300lb of delts, lats and gut, but have no arms or legs!