I won't claim to be an expert in copyright law, but I do consider myself a logical thinker. Thinking this out a bit, I don't see anything in the ruling that forces a digital distribution platform to allow another user access to a game license bought by one of its other users. The license to a game can be transferred to another user, but access via a digital distribution platform is under a completely different license. The ruling may force the likes of Steam to allow user account sales, but it does not in any way look like it forces Steam to allow a different user access to a license you've resold. Theoretically, as you no longer own the license, Steam could deactivate your access to the game while the new owner is forced to procure the game files and installation methods independent of Steam.
In fact, it would be like buying a new game from Walmart and then having a law forcing Walmart to resell that game for the purchaser, deliver it to the new owners house, set it up for them and ensure it is in brand new cloned working order, and then provide all the monies to the original purchaser. It makes zero sense. Walmart sold you the game and if you resell it, it is up to you to figure out how to get it to the new owner and its then up to the new owner to have a method to use it.
Oh and there is a little United States Court of Appeals for the Ninth Circuit ruling (basically then upheld by the Supreme Court) for Vernor v Autodesk in the good ole' US of A which pretty much puts the kibosh on the reselling of software licenses.
Even if we were in fairy-tale land and the resale of used digital games was allowed, I wouldn't want it. The sale of used physical copies of games already forced developers into the models we currently have. Downloadable content (DLC) and the piecemeal sale of games is a direct result of developers looking at ways to get around used game sales. Every developer now is building or has built online service platforms around their game franchises to lock features behind pay walls.
I much prefer the path the PC gaming industry is actually on: free 2 play (F2P). Players want to pay for games and are more than willing to happily spend away on games that keep them engaged. The F2P model allows them to try before they buy and then show the developer in a tangible way what they like about the game.
There is so much doom-casting about the current gaming industry that we are all missing the fact that the PC gaming industry has completely transformed itself over the past two years. Reselling of digital licenses for digital games would be a huge derailment.