We’re already seeing DEI weaponized. Any non white male person in charge of an organization that makes a mistake will be labeled a “DEI Hire” accurately or not. Organizations will be risk adverse and only hire the most boring white dude they can find from central casting. Whatever you want to say about diversity initiatives this will be a pretty terrible outcome.
The claim is simple: using words to mock a group, hurts that group.
This is still true when the group is one that you consider to "hold almost all the power".
Holding power is irrelevant to the harm caused by actions like insulting people or discriminating against them.