Why is that ridiculous? Seems like a totally fine solution to me. Probably not possible in most cases due to licencing issues, but if not this is the best thing a developer could do. And making games and/or their servers open source isn’t even the only option. In most cases it will suffice to just provide server binaries and patch the game to make it work with self-hosted servers, or just patch it to make it playable offline. It’s that simple. Developing games with that in mind from the beginning makes this even easier.