I was wondering because I am feeling like making an Open World rpg with roguelike elements but you play it as an ASCII game in the command line or something similar to what the nethack game used.
Why would it have to be a web-based game? You can make it any way you like. Itch.io can handle it just fine. In fact if you make a downloadable game, multiplayer should be easier to handle than if it runs in the browser.