RPGs and MMORPGs are interesting genres for different reasons.
The RPG genre has largely died. By that I mean we have Bethesda games (notably Skyrim and Fallon 3 and New Vegas were huge in their time) and that's... about it. Well, apart from Baldur's Gate and Mass Effect I guess. We used to have a bunch of other franchises. Bard's Tale, Wizardy, the TSR D&D games, Ultima Underworld, etc.
A lot of RPGs are now real-time games. A lot of people, myself included, prefer turn-based RPGs because they're more "chill". But that genre largely doesn't exist now. This is a problem in strategy games too where Civilization is really the last big holdout for turn-based strategy.
And personally I hate the Bethesda character system.
MMORPGs have had 2/3 standout successors: Everquest then World of Warcraft (and arguably FF14). The gaming landscape is littered with the corpses of EQ (then WoW) challengers. It's interesting to ponder why but also the challenges of this genre.
MMOs are seemingly built on a "vertical" progression model. That is, newe content occurs above existing content to give something new to existing players. But this creates a greater barrier to entry to new players. This means the game makes earlier content faster/easier but that makes previous content meaningless.
EQ recycled old content with TLP (Time Locked Progression) servers to relive previous expansions. WoW has followed suit in recent years, first with the release of Classic WoW (which was massively successful) and more recently with LTMs (limited time modes) of older expansions (eg Mists of Pandaria Remix).
But there are huge challenges to palying multiplayer persistent games and this has been true for the entire life of the genre. Trying to find people to play with that want to do the same thing is a challenge. EQ and WoW focus on raids, which involve getting 10-72 people to be at the same time and place to tackle content. That's a logistical nightmare and an anethema to casual play. So play has skewed more to the solo or casual player, which creates its own problems.
The big mistake challengers made is focusing on user-generated content, namely PvP (player-vs-player) content. Studios like this because, done right, it's an endless stream of content and it's realtively cheap content too. The problem? 90% of MMO players have zero interest in PvP and this is borne out by the abject failure of PvP MMOs as well as PvP partcipation in WoW.
I played EQ (starting in 1999) and, much later, WoW. I really don't know how you rescue this genre but I think you need to find a balance between persistence and seasonal content. That is, persistent game state becomes an albatross around your neck. But if you invalidate someone's effort with new seasonal items, it disincentivizes people grinding out that gear and content.