They wouldn’t need to release the whole stack to satisfy the requirements.
Thats literally what I just outlined as what would have to happen.
Release the dedicated server executable and patch the game to allow direct connections to servers.
Oh yeah, just do that, as if that's a super duper easy task to do.
Sorry mate but for most games doing this would mean the game just doesnt even work anymore, because "direct connection" means no concept of an account anymore, and if everything is tied to your account, the whole damn game doesn't work now.
If the game in any way shape or form has any concept of a "login", you are already screwed without any easy solution.
It’s an API. Unless they hardcode the IP address it or use certificate pinning, it can just be reimplemented.
Sure, that's valid, but thats one piece of one example
Now realize that a single game may have several of these APIs it depends on because thats how we build stuff nowadays, so you have potentially multiple things you need to re-implement from scratch. It's possible, sure, but by this point you've effectively remade a very large amount of the game from scratch so who cares now.
Quite often a "Game server" could be dozens of separate pieces, and maybe a couple of those could be released, but even then what if parts of that executable have still in use proprietary pieces that are used in other games they own?
You just can't apply these sorts of rules to software, they arent physical products and they don't work the same way.
It'd be sorta like if discontinued and you demanded they open license the entire car, even though maybe 60% of that car's parts are proprietary things that are also still used in
So if you tried to force them to open license you'd be also demanding they open license parts of
And you can see how that's not gonna be good for them.