Back in the early 2000s, that scene was HOPPING. A whole bunch of mods were around, some of which seem to have disappeared, particularly Armored Warfare Evolved.

A couple of things happened (at least to my perception): a bug cropped up in the Apocalypse mod where hitting a small shop would cause it to burn for over a minute, disrupting multi-player game play, and on the servers there was an invasion by trolls complete with Nazi avatars, who drove players away (myself included).