What that tells me is that the forces creating the HN front page don't have much to do with changes in the userbase over time. That's interesting, and I think to most people (me included, and pg probably included) counterintuitive.
My memory is hazy but I probably found out about HN via Slashdot or via Michael Arrington's HN post [0] from Mar. 10, 2008; so I have been reading HN since before Dec. 13, 2008 and still come back because of some really good conversations that can be had here, compared to elsewhere on the Internet.
0: https://techcrunch.com/2008/03/10/little-known-hacker-news-i...
After all, if you changed HN into a My Little Pony discussion site you'd lose 98% of old users, retaining the 2% who like ponies - and thereafter, 100% of remaining old users would like ponies.