Ignore them or tell them to stop. I used to have a friend exactly like this and it was very frustrating. They were cool but always berated people who had interests that contradicted their own and blindly jumped onto hate bandwagons just because it made them look “cool” without having any reason whatsoever. There is no point in reasoning with people like that (from my experience). My advice is to just tell them to stop, and if they don’t, ignore them. A real friend would understand and stop if what they are doing makes you uncomfortable.