Hope it's alright if I copy paste my reddit comment here
Does anyone have a good, extremely retro style MMO that's still got a relatively active community? Ideally still being supported though obviously fair enough if not. I want something like, Everquest, Ultima Online, maybe FFXI. Where the grind is there and it's pleasant, but it's also about just existing in that world. Finishing quests and exploring being the focus, over end-game raids and content you'd get out of Modern WoW and FFXIV.
I've played XIV, Guild Wars 2, and a bit of WoW during Shadowlands. XIV gave me the best time of Raiding I think I'll ever have, and I'm actually explicitly not looking for that sort of gameplay again, at least not as a main goal. Guild Wars 2 still reigns as one of the best MMOs I've ever played for World Bosses in a casual sense (mass players, more about numbers than skill with a neat commander system) and WoW I ended up having more fun exploring old expansions and towns than playing the modern content. Chatting with veteran friends and using it like a living museum lol.
That's why I specify semi-active community too. I'd love to be exploring these places while I level, and actually running into and chatting with other players. That's always been the difference between an MMO and something like Breath of the Wild for me. Rather than just googling "how do I do X," I prefer to open Map Chat and see if anyone knows the answer, or can lend a hand with a fight.
Do feel free to consider this as an opportunity to pitch the somewhat low profile or fan-managed MMO you or a friend you know plays. I'm aware there's a non zero chance I end up on like, those fan created servers for Star Wars Galaxies in answering this question. But I'd love to get an idea what people think and suggest as possible options.
I should add, I tried OSRS, not for me. Even though I know it's pretty damn close to what I want.
Tab-Target combat is preferred, though I'm not averse to action stuff.