This is a definition of censorship that removes any useful descriptive meaning from the word. It's not censorship when I refuse to listen to offensive things or refuse to repeat them to others or allow you to graffiti it on the side of my house. Similarly, it's not censorship when a private company declines to let you use its private resources to say whatever you want.

The difference between these types of "censorship" and scary, actual government censorship is that GitHub doesn't have the authority to hold a gun to your head and compel you to be quiet. You can take your repo and host it privately and say whatever you want. Comedy Central didn't have the authority to compel Trey Parker and Matt Stone to be quiet. Parker and Stone could have terminated their contracts and posted a Mohammed cartoon through some other channel.

You rob censorship of its depth of meaning -- compulsory silencing by force -- when you apply it to private actors choosing not to use their private resources to promote others' speech.

I could defend my stance. I think you're probably smart and probably know almost everything I'd say. If that's the case then we're resigned to agree to disagree.