They could have just left it in people’s libraries with the option of people using community servers, something that a lot of gaming companies have traditionally done. They give the server software to the players, who then spin up community servers and keep the game going. There was literally nothing stopping them from just leaving a game that no longer functions in the Steam library.
You can still buy Titanfall on Steam and have it in your library and last I checked, multiplayer for that game hasn’t worked in years. EA isn’t pulling it from people’s libraries because of that.