I would be fine with companies killing their own online servers, as long as they release the server software.

I don’t know if this example uses the actual software or a reverse engineered software, but back in 2004 Epic Mega Games released a small game called Unreal Tournament 2004, Epic has done a lot of shit since, but they have kept the master server for Unreal Tournament 2004 online since 2004 untill the spring of 2023, that is 19 years of unpaid server time, that is amazing.

But when the announcement came that they were shutting down the master server, the community responded by setting up their own master server. It works fantastic, you make a small edit in the config file, and boom, it just works, and since the game server softare exists, people can still set up their servers as before, and they will be listed on the new master server.

So because the game server software was released, and a new master server was set up, the game still works like it should, and is still as awesome as it ever was