That's not the reason.
Funny how some ideologies can be "fought against" safely here and others can't be. Climate change denial, a-ok. Criticizing china? It's for freedom! Labor unions? Fair game. Want to openly defend fascists? Go right ahead. https://news.ycombinator.com/item?id=20961603
Criticizing Carmack working for Facebook? now that crosses the line.
Look man, I don't expect you to go against your boss's wishes and allow discourse that actively criticizes their actions, but don't come in here to try to sell me a different story.