Only two White bodybuilders qualified for the open?

Flex Lewis could have likely qualified for the open had he went that route, but he is doing the intelligent thing and opting to become the champ in the 212-lb class. He would definitely be top 10 in the open, and possibly even top six.
I used to think Black dominance in bodybuilding was pretty clear - consider that since 1984 only Dorian Yates and Jay Cutler won the Mr. Olympia. So a little over 10 years ago before Jay Cutler won his titles, it just seemed clear to me that Hebrews were the superior bodybuilders. In the 33 Mr. Olympia competitions from 1984 through to 2016 inclusive, 10 Mr. Olympia titles went to White champions and 23 went to Black champions.
Then you have the "socioeconomic" argument, but usually such arguments predict very little - it's not like it's hard to find a weight room and lift weights. It would be a little different for something like hockey, where the price of equipment may prevent poor parents from involving their children in the sport.
But this year - damn. Talk about sheer beast domination by Hebrews. A couple more Hebrews, and you would think you were looking at a list of 100 metre sprint competitors.
