You're absolutely right, but unfortunately we can't customize HN that way; we need a general approach.
The problem is that no one, not even those of us who spend excessive time here, sees every thread or even every major thread. HN's front page is a tiny aperture given the firehose that flows through it. We added 'past' to the top bar a few years ago to give people a way to catch up on the biggest threads they missed. Unfortunately relatively few people use it. For example, this month about 4% of logged-in users who've viewed the front page have also used 'past'.
The problem is that no one, not even those of us who spend excessive time here, sees every thread or even every major thread. HN's front page is a tiny aperture given the firehose that flows through it. We added 'past' to the top bar a few years ago to give people a way to catch up on the biggest threads they missed. Unfortunately relatively few people use it. For example, this month about 4% of logged-in users who've viewed the front page have also used 'past'.