Don't compare the whole world to private property. When someone comes along and complains "Hey you censored my post" their response amounts to "We control over what is acceptable on our site". At that point haven't they just taken responsibility for all the content on their site? I suppose they could claim they're going to censor certain things on certain high profile accounts as a policy for [reasons]. Maybe?

Bad analogy, corporations aren't citizens.

Could you explain why corporations are responsible for everything on their platform if they police it to any extent?

Because policing content based on political opinion is editorializing.

Actually...