Well that (it not being fixed anytime soon) is a big problem.

a lot of this discrimination appears generational and likely won't be solved shortly by this method of self-correction.

Actually, the evidence is otherwise. For example, in the linked post:

Traditionally, high tech has been dominated by young Caucasian and Asian males (go back another 20 years, and it was just Caucasian males). Like many other parts of society, entrepreneurship has become more inclusive.

Additionally, the "typical" YCombinator startup is full of young people (who often are male). The "it's the old generation" argument doesn't stack up, and the "wait for them to die" solution is unacceptable.

It's hard to see how either of these groups are easily changed by blog posts, "awareness" of the issue, or even pure coercion.

Actually, it does seem to work. Find me an example of a startup that acted in a sexist way and continued that behaviour after it was highlighted.

The truth is that awareness is one of the things that has been shown to work, and even if there are additional things that can help additional awareness is not a bad thing.