Earlier quoted context omitted.
GitHub has, since the Horvath incident, made it pretty clear what kind of person they want to hire. And, frankly, that's fine. There are plenty of places where I, as a competent white male, can get hired and promoted without difficulty. The fact that Github isn't one of those is not a systematic problem. More power to them.
At what point does it become a systemic problem, though? Github is a major software company, and there are similar signs at other major companies, most of whom are starting down a similar path.
The problem will self-correct at some point once the lawsuits are filed and the cost of such efforts is visible to executive leadership and investors. Even if they settle the suits early on, it'll still be a very expensive lesson. Workplaces with problems like Github is apparently developing rarely get better on their own without first experiencing the consequences.