Fallout 4 is ten years old and just recently was sold again as a remake, basically a small update with pre-included mods. Skyrim is 14 years old and I'm sure it will be resold at least one more time before TES VI is released.
Moddable games are like prescription pills that add one ingredient to a patent-expired recipe, to repatent it as new.
I'd extend it to all copyright but instead of "active development" make it a nominal fee every 10 years, so anyone that doesn't mind their work becoming public domain 10, 20, 30, etc years later can easily let it go.
Most IP owners would pay the tiny fee just to hold onto IP rights and do absolutely nothing with it. If I were designing this hypothetical legislation I'd make it 10 years without a release that works on new hardware and the copyright is lost. This would at least incentivise the owners to do remasters just to hold onto the IP, something that would make them a few bucks anyway.
Note that GTA V is now 12 years old and still sells ~20M copies per year. So that’s going to be a tough sell in some cases.
You could argue it’s still actively developed, particularly due to online, so fair enough.
But that’s also sort of true for Vice City. They’ve released mobile version (playable on Netflix) over the past few years at least.
Nevertheless, I’d be thrilled if that was a standard practice.