2015 was probably the best time. Whenever I think about the past few years I don't really see myself and the 550 hours I have spent on PUBG, or the 500 hours on R6. All I see in my mind is the days and nights I would spend playing Fallout 4 and Halo 5 in my old living room. Such amazing games despite their flaws. The titles released in 2015 are what really saved me from the addiction I had to MC and CS:GO.
This list is a little screwed to be honest, Fortnite shouldn't be on the 2018 list, its from 2017 (It's also a bad game, but that's just my opinion). And Forza Horizon 4 should be on the list as well, it won basically every Racing game of the year award. It seems like racing/sports games get their own special treatment when it comes to the highest award of the year.