Users with negative points aren't hidden from the users list. Here's an archive from 2010 showing users with negative points on the last page of the user list.
The reason you don't see them in 2025 is that the users list is stuck on a maximum of 334 pages (the boundary of 20,000 users), likely for server-side performance reasons. Our total of 57,000+ users is enough for nearly 1,000 pages, meaning page 334 falls in the middle of the ocean of "20 points" users, preventing you from seeing anyone on negative points.
Notwithstanding quirks with the user list, the figures on the front page of the main section are generally correct, and do include users with negative points. You can trivially confirm that by seeing everyone's favourite sassman is 57,111th in the rankings, which is the same number on the front page.
Generally speaking, the site has no censorship of people with negative points, although we used to show negative points as zero a long time ago, as seen in this archive.
You will notice some discrepancy with the user count on each section, which is a quirk of the site's setup where three instances of Q2A point to the same underlying user database.