Will be wildly ironic if Apple pulls uno reverse card and eats Kotlin on Android instead of the other way around.
Which ironically would be just like Flutter, totally bypassing any native UI.
My gut feeling is both teams probably have a plan for steamrollering the other in the event of anti monopoly measures forcing each to accept the other store. I.e. it is conceivable you could launch the Play Store on iOS and run a significant proportion of Android apps through a compat layer.