Not going to spend an hour watching a video.

The medium link says nothing about women and minorities specifically. It's a critique of flat management structures in general.

Another source from 6 years ago: https://youtu.be/41XgkLKYuic

It seems like the flat management structure allowed an ad-hoc hierarchy of cliques to form in the office anyway, pitting entrenched teams of old-timers against new hires, but implicitly. When you think of the lack of support for TF2 over the years, this is illuminating.

It's astounding that Valve/Steam are still as successful as they are in spite of this culture.

The second link is paywalled, but from the various sources I looked at, the diversity problems with Valve seem limited to "Valve refuses to spend company time/effort to support my cause". I have not seen any concrete claims of misbehavior, in direct contrast to some other video game companies.

Additionally, when I actually look into the alleged statistics of claims that "Valve is primarily white and male", the numbers ... don't actually look that bad? We shouldn't expect any company to fit national demographics exactly.