Police brutality and the war on drugs are both important issues. You can draw attention to them and draw attention to the fact that they disproportionately impact Black people without getting angry and shouting people down any time they try to point out that they do in fact impact other people as well, though maybe not as much.
Screaming at other well meaning liberals is one problem of the BLM movement.
The other is that they are too enamored with BS privilege checking politics. They have real, legitimate issues but they deluded when the same people complain about BS like "white people are so racist because whenever I go to work with a giant wig glued to my head, they sometimes ask if they can touch it."
Well said. There is a difference between calling attention to one's policy goals and denigrating anyone who thinks that they have gone too far with their rhetoric. I agree that the war on drugs is bad and that it disproportionately affects blacks. There's also a disturbing number of black people dying during police interactions. I agree with their base ideas, but when you have people going around complaining over every "micro-aggression," it really sours people's views.