My second problem with Flutter is the writer's apparent biggest positive feature — Dart. (I love how he naively states that Dart was conceived as a language to transpile to Javascript; it was conceived as a replacement for Javascript with transpilation as a stopgap.) I think Javascript is a fine ("good enough") language that (a) works almost everywhere and (b) is evolving at a more-than-sufficient rate. I have no desire to drink Google's Kool-aid. (Go, OTOH, I am fine with.)
But then I get to "Building Layouts with Flutter":
https://flutter.io/tutorials/layout/#step-1
This makes the articles I've read on "thinking the React way" seem mild in comparison. In exchange for having to restrict your layout ideas to the stuff that will work in Flutter (which first entails somehow grokking what works in Flutter), you have to go from visual concept to hierarchical breakdown and then translate that into code in less than intuitive ways, and then when your graphic designer decides that such-and-such needs to be 2 pixels lower or the stars should get bigger in the middle, you're still going to be hosed or inserting fixed height shims all over the place (and how will that look on a tablet?)
This API seems too high level to produce polished products. Of course it's alpha so blah blah blah but being able to quickly produce generic stuff is not a proof of concept, especially if you can't then refine the generic stuff to the nth degree.