I think you're right, but I think this doesn't address what I suppose is a reasonable fear: engineer a significant enough advantage to out-compete a rival population, and then only later rediscover the need for diversity. That doesn't work out well in the long term for either population, but that doesn't mean that, given the choice, it wouldn't happen.

Given the Chinese example, I'm immediately reminded of the folly of The Great Leap Forward and Chinese steel production quotas, and their results.