Here's the thing, as I said in another response: Protests are supposed to be peaceful. But, if someone is trying to agitate the crowd, police have a duty to remove them. That is called de-escalation. Now, we don't know if these people would have done more, but there are countless times in history when shit like this happened, and peaceful protests turn on a dime. We don't know everything that Ezra said or did. Does he have a right to say it? For the most part, yes (as long as it isn't hate speech), but at the same time, the police have an obligation to allow a peaceful protest to continue and avoid the chances that things could take a turn for the worst.
Believe me, Ezra was there to agitate some sort of reaction. It would either be him getting yelled at, hit or arrested. And, I'm fairly certain he was prepared for all instances and had a fundraising email drafted to take advantage of this.