There's such a thing as sports watching, when you're associating yourself with a team and are glad and sad together with them. I guess something like this could happen elsewhere...

If you don't praise Elon Musk he will say bad things about you on Twitter

Because of the popularity of the ‘I’m no Elon fan’ preamble on HN.

Let's flip it: Why do you care? Does it really bother you that much?

P.S. Wait a second, why do I care about why do you care? Oh god...

It was just a reflex and a sports team rivalry is a good analogy. In other forums on the inet there's definitely a team spacex vs team blueorigin feeling. Think about American college football, imagine someone at UT congratulating A&M for scoring a touchdown. That would require finesse in some crowds :)

> Why do people feel the need to

Whenever it's used, it applies to the comment using it as well as the comment it's referring to.

It's a way to add emphasis on "They did a good job". We could translate it as

"I'm somewhat biased against BlueOrigin, but BlueOrigin managed to overcome my personal bias with how impressive their launch was".

It's similar to saying "I normally don't like country music, but that was a good song". In that sentence the intended message isn't "I don't like country music", instead it's "I liked that song"