You're about to have one less option for card games on your console. CD Projekt Red has warned that it's shutting down Gwent on PS4 and Xbox One to focus on the PC and mobile versions. Between the recent release of the Witcher-themed title on iOS and its upcoming Android edition, there would be too many versions to support while still "improving feature parity between them," the studio said. You'll have a while to keep playing, but you'll start to notice the shutdown process very quickly.
To start, real-money purchasing has already been disabled. CDPR will subsequently patch the console versions on December 9th to "freeze" them in their current state. From then on, you can visit a website to transfer your progress to a GOG account (used by both the PC and mobile versions) without any Gwent progression. All matchmaking with non-console platforms will go away, too. The game itself will stop working on PS4 and Xbox One until June 9th, 2020.
The developers noted that the PC and mobile editions were the "most popular." In that light, this is really triage to ensure that CDPR supports the widest possible audience without compromising on quality. All the same, this is bound to be frustrating if you're a Gwent console fan. You'll have to either switch to another title on consoles (not always an easy choice) or accept that you'll be playing on another platform from here on out.