Because shes politically incorrect.
They dont fire any of the hags on the view that laugh and make jokes abouta guy getting his penis cut off. No late nite liberal hosts get fired.
If they agreed with what she said, theyd find a way to keep her.
Disney has several billion reasons for firing Barr over this. That's what they expect to take in from the Black Panther sequels and the Star Wars sequels, and all the other movies, shows, and theme parks that they own. Keep her show and they risk a boycott of those that could lower their returns. Political correctness may be the excuse but the reason was business.