The former employee used one particular story to describe things at the company that generally made them uncomfortable over the course of their 5 year tenure there, including their coworkers’ reaction to news events that affected them, and hiring practices that they perceived as biased (“reject candidates of color because of “fit””).

The former employee then makes several suggestions, including rethinking hiring practices, providing more robust diversity training, and additional counseling/support for underrepresented employees.

You can debate the validity/truthfulness you perceive in the employee’s account, you can debate whether you think the suggestions are good or not, but saying this isn’t an employer based issue seems like just putting your head in the sand.