With gog? of course i can. I have the files and i can give them to my family. They can then play them.
The fact that I'm "buying" a license holds as much weight in this issue as the countless eulas and privacy policies i supposedly agreed to.
We "endusers" live in a world were we are compelled, yes compelled, to enter legal agreements to do anything, and where these terms are dictated and changed unilaterally. Terms like these should and are meaningless yo everyone except for courts that foolishly hold them valid. For everything else, they should and are ignored.
From the legal perspective, you don't truly own the game on any of the platforms.
From the technical perspective, the moment the game is on my PC I can run it.
For passing games to your heir legally, there is no way.
For passing games illegally both steam and gog work.
For steam, you can download the steamdll and backup all your library and be good to go.
For gog you don't have to do that, but if we are talking of illegally backing up all your games for after you die, you are good.
As long as you are alive, you can play both gog and steam games for as long as you want.
Interestingly, you can illegally share games with your family in both platforms when you are alive, but you CANNOT legally share your gog games with your family, only Steam ones.
Couldn't this be implemented as a web extension? I imagine modifying singlefile to automatically send html to a local port is much easier than trying to convince a chronically mismanaged organization like mozilla (no offence to mozillians).
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