MUDs literally are a command line. There are tonnes of addons for MUSH still viable. The mudlet client's developer keeps banging on about how wonderfully accessible the client is now on r/mud on reddit if you want to give that one a go, though.

@cachondo yeah i know there are, but every Time I have someone who wants to play with me and they don't know how to properly set up Mushclient so it talks to them automatically, that already needs a few Plugins.

part of that is just screen readers, though.
The native read-only textbox on windows is obviously quite shitty for developers to work with in terms of styling it, so you need a way of doing an output buffer for a screen reader right there. Similarly drawing new text has no universal mechanism for talking to screen readers.
I wonder if you might find a very modern html5-based system that's as strong an app in the way the mastodon clients are, but I've not yet seen one.

@cachondo thats already where I don't know anything, I never developed native Apps or Webapps so far