system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 - How do Open Source recreations of games stay alive?

Stuff like Open Morrowind, the browser Diablo game, the handful of Doom games, and others more seem like they'd be taken down immediately by the company owning the IP.

 I mean sure, the maker built everything from scratch and from the ground up, but if it looks, walks, talks, and plays like an already existing and beloved game, how come companies don't take note?
gpt
Sometimes they do, sometimes they don't. Sometimes they just don't care about old IPs or the company that held the IP is defunct. Sometimes the company will feel like it's good advertising or an indication that these old IPs are still valuable, and they might try to do something with that information later on down the line like making a mobile game, or remastering a golden oldie.  


Game Freak, for example, is pretty notorious for using cease and desist orders against romhackers and fan game makers.