I should be allowed to criticize a company for bad practices, which is what OBS is trying to ban with these new rules. No, they are not obligated to host Venger's content on their platform, but then, they are failing to provide me a service that I want, which I should be allowed to criticize.
Private companies are not allowed to do what they want BTW. They can't for example, fire or refuse service to people based on their religious beliefs. Why should political beliefs be any different?
Now, that being said, Venger does like to purposely create drama just for the sake of it, and OBS is a platform that is pretty clear about its dislike of drama.