Are mobile stacks so specialised that it's difficult to switch between them? Out of curiosity, how long would it take a flutter dev to become productive in some other stack?
I started with Blackberry SDK plugin with Eclipse, then to Android, Windows Mobile (UWP) and iOS in that order. Majority of those projects I have worked are written in native. It's not that hard to switch since you can find familiar concepts in each frameworks and stacks.
Of course, I have been also part with cross-platforms solutions but it just cannot cope up with the yearly updates and deprecation especially if your apps are critical.