There is very little diversity in Triathlon. Anyone who tries to suggest otherwise is delusional. I'm Asian, living in Toronto - arguably the most diverse city in the world - and practically all my triathlon friends and the triathlon community at large are white.

There are two reasons:

1) Cultural factors - triathlon (like fishing, golf, cottages, hockey) is traditionally a "white person" thing.
2) Economic factors - it's expensive and thus limited to those who are wealthier. In North America, the wealth is more concentrated among Caucasians.

In order to survive, triathlon needs to appeal to more young people and a broader demographic (culturally, economically, etc). In its current form it simply won't survive and once all the old timers retire it will eventually dwindle and die, much like the number of local races folding each year.