Sorry, I was having trouble putting what I had in mind into words. What I meant by more advanced was giving the player more things to do and people to talk to. Like, say, things to do for gold and experience besides killing monsters and doing quests. I want to give players more immersion into the game. I've played a few "text RPGs" (is there an actual name for this or is it just RPG?) and it felt more like a "choose your own adventure" story than a game.
Yes, there have been many of them over the years. Those are the oldest of the RPG genre, often coinciding with physical-world RPG rule system invention, or testing grounds for rule sets.
You will need to either create large sets of rules for a world to be automatically generated or you will need to create a large amount of content yourself. A rule-based random world is going to be more replayable than a single hard-coded adventure book, but it is also much more work.
The games based on text-based graphics, with boxy rooms and letters for monsters, are called Roguelike games as Rogue was one of the oldest in the genre. NetHack is probably the most popular of these today, although many Roguelikes have very numerous followers.
One nice feature of these worlds is that designing them with multiplayer components is really not that difficult relative to making a single-player game of the same size. You don't need all the fancy graphics and animations and models and audio and mouse hit detection and all the other fancy features. A text-based view of the data can be very minimalist. Sharing the data between a small number of players is a natural next step.
The MUD and MUSH are the most common of them. A MUD is usually everybody running their own adventures mostly in parallel, a lot like how WoW has everybody running the same world, running the same pool of quests, but doing it on their own. A MUSH allows players to create rooms and levels based on rules they provide, and encourages more of the active role playing. Many popular MUSH servers are focused around groups of players who run their own D&D-style campaigns among themselves in the shared world, building up rules for sub-dungeons within the context of a larger shared world.
A good MUSH has lots of people to talk to. People have built up relationships, had virtual-marriages and intimacy, and even on occasion had real-world marriages result where they were online and had their virtual characters marry at the same time to share it with all their online friends. So there is that component, too.