I know this is a kind of provokative questions, but I need to ask:
Why not a Kotlin API to JavaFX? JavaFX really seems to take off recently. (I know there is TornadoFX, but the guy behind it is kind of a lone-soilder and it is not really a 1:1 mapping of ithe API).
And if it is about modern declarative GUIs with mobile and desktop support from the ground up… what about Flutter? o.o