>HN users have an intense emotional relationship with the front page
If a "greatest 80s hits" radio station started broadcasting music from the 00s and people got pissed off you wouldn't say "listeners of this station have an intense emotional relationship with it". When they tune in to the "greatest 80s hits" station, that's the only thing they're looking for; they don't want to listen to random songs.
You're trying way too hard to make this about bias. There are more charitable and simpler explanations, such as signal-to-noise ratio and the expectation that submissions to HN are focused on geek-oriented science and tech topics.