Seems something of a straw man argument. Women have been saying that this is an issue for a long time, across a number of companies and industries, which points to a systemic issue, not an individual's responsibility.

Different negotiation techniques can vary in effectiveness based on gender (and a dozen other things).

But you have to be in a super toxic workplace for less than optimal salary negotiations to cause wider social and team issues.

I'd say this demonstrates them being responsible: they're responsible enough to know that sexists like you are going to judge every single thing they do on the grounds of them being women instead of people, and they adjust their actions and behaviors accordingly. People can negotiate their salary aggressively. Women, evidently, can't.