Witcher 3 undoubtedly deserved the award. I know a lot of people here are trying to write it off, saying the awards don't matter, but they do. They really do. Witcher 3 is just a better game. Even though I personally prefer Fallout 4 over it, I still recognize that Witcher 3 is a more polish and better put together experience.
Fallout 4 launched with a myriad of issues that still haven't been fixed. Horrible framerates on rigs that should run the game without issue. Stuttering problems, and crashing. Slow texture loading/texture pop-in. This is the same engine as Skyrim, and it has so many of the same issues. Like, recently I've been experiencing that bug where it takes your character 10 seconds to switch weapons. I had the EXACT same issue in Skyrim. Bethesda couldn't get that sorted out in the past 4 years? We still don't have a FoV slider, so I guess we gotta mess with the ini files again. Bethesda doesn't want to support any resolution besides 16:9 and 16:10, so if you have some "exotic" resolution like 5:4 you need to install a mod. You can't even turn off V-sync without breaking the game.
Witcher 3 did have a few issues on launch, but CDPR actually put in the effort to patch their game. They released three patches in the first month of release, not counting the launch patch. Almost a month into Fallout 4, and Bethesda hasn't released any patches. Look back at Skyrim, Fallout 3, Oblivion, and Morrowind, and you'll see that Bethesda has no issues ceasing development on a game while it still has a [censored]load of bugs. Thank god the modding community actually fixes their games.
On top of the great writing, and sort of pretty good gameplay, Witcher 3 looked pretty amazing. I mean, it looks better than Fallout 4, and it also performs better than Fallout 4 because CDPR actually attempted to optimize their game. Bethesda just doesn't give a [censored].
I spent about 80 hours playing the Witcher 3, and I really have no complaints. It felt like a complete and polished game. CDPR had a vision and they executed it near perfectly. I still prefer Fallout 4 because I love the "Bethesda RPG", but I've got a laundry list of complaints after 100 hours of gameplay. Bethesda needs a new engine, and they need to stop releasing buggy, half done games.