I would suggest voluntary secondary e-mail to games to allow them to be handed off upon death, like a painting owned.
just include login/pass for your gaming accounts into your last will. sure you can't take it to grave but there's no reason why you family members can't use it. I've heard there was cases with steam when they transferred account to a sibling after they asked Valve nicely. But I see no reason why any one should ask. Neither gog or steam has scan of your ID and you're not sticking your body parts to the login box for checks :) that could be anyone with your login access and no one will care
I kind of hate being the stick in the mud, but I feel it is exactly what gog.com is about: we do own these games. We do not rent them, or temporarily posess them - we OWN our games.
And in the EU, we still do - Valve or Origin or whatnot.
Including log-in pass requires submission of your account bound e-mail, with full credentials. I want my brother to have command of my estate - not access to my e-mail.
My brother loves me dearly, that's why.
On tops: @gog.com - a few of us might die whithout gaming loving heir. For the games my bro and my best friend might not want - I'd like them to go to poor gaming inspired children, girl gamer children in particular.
My rig included.