It is definitely an interesting subgenre of videogames. Two things I want to mention:

1. Most of these types of games are made by indie devs, who are supported by their fans on crowdfunding sites (Patreon etc.). This leads some devs to update their games slowly, dripfeeding content to the players; the longer they develop the games, the more money the whales give them. It’s an interesting parallel to the many early-access games one can find on Steam.
2. It’s interesting to compare the types of stories these games tell to other independent internet creations, e.g. fan fiction. There’s not much fluff. I’d wager it’s because of demographics.