Yeah, the Arch wiki is the Gentoo wiki we lost. I was around for it and the Gentoo wiki was amazing, it was one of the best Linux resources all-around, it was tremendously useful even if you didn't use Gentoo.

This was still the case of Gentoo until they wiped/lost their wiki and didn't have proper backups.

When did this happen? I haven't seen anything about it online

From what I can gather, the event happened in 2008. At the time gentoo had no official wiki, it was an unofficial wiki that died or went offline for a significant amount of time.

<https://web.archive.org/web/20081023145740/http://www.gentoo...>

And when it came back online in november,

> Gentoo-Wiki recently had it's database lost; this is the rewrite of the site

<https://web.archive.org/web/20081204053828/http://en.gentoo-...>

I'd argue that Arch has an advantage with its KISS philosophy. For example, because manual intervention is acceptable, it keeps the distro simpler for not having to handle odd edge cases with package breakages/upgrades