No, saying "don't get politics in software" means asserting that the political influence of the name "RuboCop" is small and not significant to the project (it is significant as a signal to parties in a particular conflict that's not relevant to the project) and any discussion about it would be much ado about nothing that detracts from issues that are actually relevant to that piece of software.

Intent matters. If the name was initially intentionally chosen in order to assert a political position, that would make a difference. But if someone is requiring all the world to join in this current USA internal conflict and pick sides, then that's not a reasonable demand. The RuboCop maintainer is not part of this conflict, he's neither a victim nor a cause in this long-festering USA issue, and it's his moral right to stay out of it if he so wishes.

I have a preference towards the BLM side in this issue due to the appalling examples of police brutality, however, if someone on the BLM side would demand me to be "with us or against us" then I'd consider a profane refusal to be appropriate, I'm not applying for a membership in a tribe; If refusing unquestioning signals of support means that people become enemies of your tribe, well, so be it, that's just an indication of an unreasonable tribe.