Because the thread you mentioned is about politics. Political discussion may be allowed on HN, but most people don't like them, as they're completely non-productive and just get everyone angry at each other.
Seems silly to think that politics goes away if you just don't talk about it. Facebook recently had an entire ad campaign around reducing the toxicity on the platform - surely a discussion of that has a place when talking about earnings or lack thereof.
I'm very aware of what it means. Most political discourse in the US is currently propaganda being exchanged by both sides with no intent of actually giving consideration of what the other side is saying.
Go look at a comment thread on reddit on a news article about Trump if you'd like an example.
