> It's been used by people to harass people in the real world.

And libraries have been used by people to learn effective methods to harass or harm others in the real world. Quick! Let's shut down all the libraries!

> I think we'd agree that it's an issue that needs to be handled with moderation and the law, but it's also a real problem.

We already have such a law. It's called Section 230. Forum operators should not be subject to tortious interference, criminal harassment, or other manner of extrajudicial punishment because they choose to exercise speech that you find repugnant.