That's biased by the fact that many people who were upvoting back then have since left the site. If you want to see for yourself, the Wayback Machine is a better sample: https://web.archive.org/web/20071115044647/http://news.ycomb...

Is there an explanation of what's going on for that page somewhere?

Articles voted up by old timers.

is there a definition of "old timers" ? N years old account? signed up before year X?