That wouldn’t really work, unfortunately. Most companies don’t just shut their doors, they’re bought by someone else. That new entity would own all the company’s property. Even when they do shut their doors, typically it’s done with debt, and debtors end up buying the assets.
Most of the IP rights for those old abandoned games are split up between a bunch of random legal firms.
Makes it a nightmare to legally remaster or remake old games. Since a game’s copyright will be owned by Law Firm A, and the trademark will be owned by Law Firm B, and the art and music will be owned by Law Firm C, but then Law Firm B says they actually own some of that art and music as part of their trademark ownership, etc etc
That makes the situation easier for piracy/unofficial ROMs though, since lawyers aren’t going to do shit when they can’t even figure out who legally owns a game.