We're obviously not going to agree on the moral aspect of the matter, so I won't argue in circles with you and belabor the point.-snip-
However from a practical standpoint, I don't feel like you realize how damaging to BLM itself such a move would be. This would paint and completely reframe them as being authoritarian, as being about forcing things on people. It would make people question whether they are in this because it's right, or because they are after power. This would contribute to discrediting an entire movement doing good work for the sake of sticking it to a few kids who will not give a damn and, at best, leave that specific game. Not to mention people's knee-jerk reaction to being forced to do something and have their free time invaded by something they had no say in.
That's a bad call on top of being morally indefensible in my opinion.