ESR doesn't play that WoW. (Apparently he is fond of World of Warships, which he plays using Steam and Proton.) I think he just wanted to focus on gpsd and ntpsec, rather than maintain Jargon, especially since hacker culture a) ceased to exist as a thing distinct from the broader developer culture; b) started changing too rapidly for a maintainer to keep up.

Never let the truth get in the way of a good story!