can you explain the systres deal for me? I'm not in teso fandom, and by looking at wikis it is impossible to understand what the big deal is
in short, the systres as depicted in ESO are a way to softly recanonise some old lore about the way bretons worked from before Morrowind's* rewrite of the setting, when they were more explicitly a druidic culture
*: technically a lot of the rewriting happened with Redguard, but that game ends up in a very liminal space as far as lore goes, because it rewrote a lot of what came before it and was also rewritten a lot afterwards
ESO had been playing with this type of soft recanonisation of Arena lore for a while, and I think it's neat, but it also sticks out when it happens for the same reason it's neat: it's not really secret. the systreans being canonised as a group of bretons who carry on the legacy of the druids of galen is fanservice for people who remember the druids of galen being mentioned in Arena
what I believe the modders are getting at when they call ESO "postmodern" for referencing both itself and things outside of the game is that, because the systreans were written as a bit of somewhat tonally inconsistent fun for the mmo (here meaning "they are referencing a game from 30 years ago"), it doesn't line up with the tone they want for the semi-consistent version of the setting they're depicting in the mod. this is uniquely problematic because, for a time, they actually did include the systreans, and then they removed them
if my assumption is correct and that's what they wanted to communicate, they handled the PR side of this very poorly and made a lot of people very mad because of it
tl;dr: modders add druid bretons, modders remove druid bretons, much arguing is had and none of it matters because literally all of it is about a crusader kings mod. the appropriate reaction is to hold whichever opinion creates the funniest situation depending on which company you are in