Since the article missed this detail, here was the crowd's reaction following the trailer announcing what is apparently Valve's big game for 2018...
https://www.youtube.com/watch?v=R0qZTS38cjw
As a developer, Valve has been something of a joke in recent years, since they haven't actually been releasing games, or even indicating whether they might be working on anything. They seem more interested in monetizing loot drops in multiplayer titles lately. Announcing a mobile-friendly trading card game after years of no new game releases or announcements is about the last thing anyone wanted from them. It's like they have some aversion to releasing anything that isn't centered around trading items through Steam. The last time I felt excited for a Valve game announcement was with the Portal 2 teaser OVER 7 YEARS AGO, and the last big game that Valve announced was CS:GO, way back in 2011. I thought for sure they would have some big games to launch alongside the release of Steam Machines, or Steam VR, but there's been nothing so far. It kind of makes you wonder what Valve's game developers actually do. Design hats?
At least Gwent was derived from a game that already existed within the Witcher universe, and wasn't just a random cash-grab only vaguely related to its source material. And of course, the Witcher developers have actually been continuing to release great games, and have more highly anticipated games in progress, despite being a smaller company with much less resources.