I went to a Tesla protest. It was entirely peaceful. I personally don't fault someone for buying a Tesla, particularly before Elon went loony. My goal for the protest is to bring to attention the fact that the owner of that car company is party to the authoritarian takedown of my country, and that people should not support that company any more if they can avoid it.

I agree that vandalizing peoples' cars is illegal, I don't think it is practically useful, and golly gee, we still have a criminal justice system (for now) that can be used to punish those who commit acts of violence.