There are also video games in libraries, and there are books in libraries with components that are unusable these days. Nobody is required by law to support these components in perpetuity. Nor is any publishing company required by law to maintain support for a book in perpetuity in any way.

Nor is anybody required by law to help you fix your classic car. People with classic cars spend tons of money to find spare parts or even get them manufactured. This is despite the fact that cars are much more of a necessity than video games.

Likewise, if you paid a video game to keep their servers open, or paid them for their source code, they'd give it to you. If you paid a smart person to reverse engineer the network protocol and write an equivalent server, you'd have your part.