GOG is getting a nice little pr moment off of this but you're getting basically the same license, no matter where you buy the game.

The root of evil in digital distribution is the DMCA anti circumvention clause: it is illegal to circumvent a DRM protection to gain access to some copyrighted work, even if you in actuality possess a license to the work. This law gives big platforms far too much power to control how you interact with their products.

It should be legal to modify a work to allow it to be played offline, to make copies for archival purposes, to fix the work to run on newer platforms, etc. As long as you have a license to the work you should be allowed to take steps to ensure your rightful access to it.

By the way, the root beyond roots of evil in digital distribution is the insane length of copyrights themselves. Why are patents 20 years, but copyright extends to 120+? The answer is pure greed.