In Patch 6.2, many instances of "Beastman" and "Beast Tribe" were changed to "Tribal" in UI elements and other non-dialogue text in the game. However, it appear that Triple Triad was skipped in this effort. The card type is still called "Beastman" and certain card descriptions still use Beastman when it wouldn't make sense to do so.
The change to Tribal Quests was a metachange to allow the game's tribal quest system to more reasonably include factions that are not beastmen, such as the Dwarves and the Omicrons. It was not an erasure of the term or concept of beastmen from the lore. People in-universe still refer to them as "beastmen" or "beast tribes", and so it would make sense for a mostly-in-universe card game to continue to use "beastman".