Totally agree. The students can leave. They will get a zero. They will fail the course. They will eventually have to drop out. That's the natural order of things.
But let's not pretend you can have a conversation with people that do not want to have one. The problem is these idiots also want to pass the course they didn't attend and didn't learn anything from or they want the course censored. Either way, by making these demands, they are the ones attacking students who actually put in the work to learn and students that want to actually learn and not get rid of classes or lessons they don't agree with. No matter how you look at it, it ends up in censorship if you begin to entertain the ridiculous censorship demands of students.
If I was the school's president, I would make sure these people who disrupt class and attack other students' freedoms fail for their lack of work and get kicked out for their attacks on education and other students' ability to obtain a proper education.
Have the president say to the student: "You don't want to participate in the discussion? Here's a fucking zero. Now get the fuck out of my class and if it continues, get the fuck out of my university. Most people here are actually here to learn, not disrupt the education of others." That's basically what U of Chicago is saying ahead of time now and what most universities refuse to say because the money is so plentiful right now.