We know the reach of the mobile market; playing Balatro on my phone lets me play anywhere, anytime.
I think adapting the interface for portrait mode would make gameplay more comfortable, accessible, and very appealing to players. Some games have done it, and it's very fun.
I don't know if it's possible, but it would be a great improvement (pls jajja). 
#Vertical screen mode for mobile
compact python
edgy sedge
Kinda unnecessary, but it would be radical
brazen laurel
I've seen some mock-ups for it. I'd use it. For a non action game, the option would be nice -- even if it's optimized for landscape.