oskar, let's assume the world is made of lots of panda bears, lots of grizzlies, and a few polar bears. The polar bears set up a system that oppresses both, but the pandas get it worse. So the pandas get all pissy and start saying "panda lives matter", which makes the grizzlies somewhat aware of the problems pandas face, but doesn't really get them on board. Imagine how much more inclusive the message would be if it was "fuck the polar bears". Maybe instead of trying to make the grizzlies feel like they are "privileged" they made them realise they too are oppressed by the polar bears.

The problem is that the pandas blame the grizzlies for their problems, not the polar bears. They are appealing to the guilt of the grizzlies, instead of trying to get rid of the polar bears.