There is a culture of managers who are not well-versed in either people management or DEI. That means that your leader who may be girlbossing it up on LinkedIn to create her personal brand may be holding onto sexist managers who are reframing normal work disagreements as cat-fights between women.
Also, remember, there is a difference between a culture of "nice" which is very superficial, and a culture of kindness that shows concern about people. In some parts of the company. There is a culture of "nice" pushing out a culture of kindness.