Black Lives Matter is not a "group," it's an idea. If you disagree with the idea then you are irredeemably evil. There is no argument.
"you can't say ANYTHING these days" is an immature way to process the notion of other people having opinions or reactions to your ideas.
Related: it's really easy to add female characters to your story's cast. Step 1: give a damn about women. Step 2: write.