Fuchsia is an OS that is also using Flutter for their entire UI layer.
I think there’s more a case of there isn’t an argument for doing but rewrites just because Flutter is now a thing but in a greenfield scenario it would be a serious contender
But that’s not demonstrating the promise of a great cross platform experience.
I have some context as to why it’s both a wrong and misleading statement.
When it came to the biggest money maker of the entire business this is what they picked. When it came to a new greenfield project for an entire OS… this is what they picked for the UI.
The statements you made about “the lessons they learned” is just some stuff you made up and isn’t actually supported by facts.