Belittling them is the only approach that will work. They have such a thin skin and fragile egos that making logical arguments, following procedure, or addressing this via well established "norms" just results in them getting their rocks off on telling you to F off. See [0] just as one example of many.

On the other hand, pointing out the lunacy of their actions, their hypocrisy, and malice through satire, parody and straight up bullying is the only way to truly break through the shell they've built around that fragile ego they're carrying around. Just my opinion.

[0] https://shop.gop.com/products/liberal-tears-mug