> Freedom of speech means the government cannot limit what you can say. A private entity, such as Blizzard/Activision, has no such obligation.

This is absolutely incorrect. To Americans, Freedom of Speech is, as the person you're replying to said, an inalienable right of all human beings. It's a fundamental principal of our society. The first amendment is a legal constraint on the US government that keeps them from violating that right. It does not grant the right, the right belongs to all humans simply from the nature of being.

Think of it like this. People don't think murder is wrong because it's illegal. We have laws in place making it illegal to setup how government handles murder, and we want those laws because murdering a person is wrong at a deep and fundamental level. The laws follow from the underlying ethical beliefs. Freedom of Speech works exactly the same way.

So a company like Blizzard censoring an activist is not a violation of the First Amendment, but it is arguable a violation of Freedom of Speech.