Sis compares men/women to white/black and thinks our activism is silly because it just nullifies theirs

She brings up the example that "Black lives matter" as hi-jacked to become "all lives matter". Men talking about their problems is like a white guy talking about their problems to a black guy, who has it much worst.i.e. racially profiled, etc.

How do I explain that she is ridiculous. She thinks the whole men-rights activism is silly. This irritates me so much.