Gwent was quite generous with their free stuff and had a ton of balance changes, which might have been their downfall. The game changed a lot compared to what it was in Witcher 3, only the basic rules were the same, which made it hard for people to learn. Not having a mana/energy system meant they had to create a lot of systems to balance cards, and that made it even harder to learn.
It was a really fun game tho, and the foil cards being animated was a really cool touch.