The context is somewhat different on an anonymous online forum such as HN. Giving feedback as a stranger can be fraught with insufficient information. Criticism can easily spiral into negative flamefests full of assumptions of the receiving party. Thus, mods try to dampen it from getting too negative and toxic.

> So why is it any surprise that every startup company has precisely the same back-patting culture?

They are different because presumably coworkers are people you at least personally know in passing, and are not anonymous usernames.

We should be gracious to strangers but more critical to those whom we do know.