What? How does arresting and punishing innocent people deter anything? You’d have a point if the police had separated the bad apples from the good ones, but the main point of the article is that they didn’t. They arrested anyone who was in the area and charged them all the same without giving them a chance to leave. Did you even read the article?
Beyond that, it’s not the job of peaceful protesters to stop violent protesters. People are responsible for what they do, not anyone else. And the mistake is with people who want to lump all the apples together, good and bad, as an excuse to punish apples. But when right-wing extremists kill cops, it doesn’t mean every conservative is a cop killer. Only the people who did it or incite them.