And how you would craft a law to prevent a company from forming sub-companies for specific games to isolate risk? Or make it illegal for a company to go bankrupt?
Creating sub-companies is common business practice that even small businesses use. Like if a small company wants to buy a building, they may form an LLC to hold the property to isolate that risk from the rest of their business.
Sub-companies are owned by companies. Don't cap liabilities to the limited assets of a sub-company that actively violates the law.
Or cap them to a reasonable standard: 100% of revenues derived from the game.
I don't know how you'd craft that law--I'm just saying they should. How to encode the spirit of the law into the letter of the law is the job for legislators.
Whenever the topic of regulating companies comes up, there's way too much fatalistic "Oh dear, we can't possibly incentivize good corporate behavior because companies are oh-so-clever and there's just no way to handle all the edge cases they will exploit!"
We'll never get anywhere at all if we simply give up the moment someone forms a shell LLC.
Bankruptcy process already involves identifying and administering the company's assets, so releasing the server software (as-is) to owners of the game could be part of that.