@Ialyrn yeah, the charts are only for Steam. The article though is not, and the data seems to be self-reported by EA.
GSD digital data includes games from participating companies sold via Steam, Xbox Live, PlayStation Network, Nintendo Eshop. Major participating companies are Activision Blizzard, Bandai Namco, Capcom, Codemasters, Electronic Arts, Embracer Group (including Gearbox, Koch Media, Sabre Interactive), Focus Entertainment, Konami, Marvellous Games, Microids, Microsoft (including Bethesda), Milestone, Nacon, Paradox Interactive, Quantic Dream, Sega, Sony, Square Enix, Take-Two, Ubisoft and Warner Bros. Nintendo and 505 Games are the notable absentees, alongside smaller studios.Digital data includes games sold in Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Russia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey, Ukraine, and United Kingdom.
Physical data includes all games, but only those sold in Austria, Belgium, Denmark, Finland, France, Germany, Italy, Netherlands, Norway, Poland, Portugal, Spain, Sweden, Switzerland and United Kingdom.
May not include EA own storefront, but given the inclusion of PS Store, Xbox store and physical copies, I guess the trend is solid enough to extrapolate to other vendors as well?
It was mentioned by someone above the possibility of Steam users migrating to consoles as well. I don't think that makes for a significant cohort. More often than not platform is chosen by convenience and that decision tends to stick. Once I feel comfortable playing on PC, perhaps even having my own compatible wheel and such, I wouldn't consider jumping to a different platform unless it is just as convenient as I've made PC to be.