His job required him to participate in a team setting. His speech made that untenable according to his employer.

He hasn't been silenced though, if anything his voice carried far further than intended.

I'm not sure Google did the right thing here. The argument that this is the precise sacred cow he was talking about is strong.

But it isn't censorship. His speech wasn't abridged. He isn't in jail. There is no freedom from reaction, nor is there a freedom from outrage. If he had sent out a racist tirade, dropping racial epithets, would you still say his right to free speech was infringed when he got fired?