> it completely sidesteps a lot of the platform-specific woes
This is the key point where Flutter wins over both React Native but also the native Android and iOS toolkits. When you design a screen in Flutter, it will behave as you expect on every different version of Android and iOS. You just check it does the right thing as screen size changes (which is usually pretty easy to implement, and very easy to test) and then you get predictable behaviour. It is so rare that you need to fix X screen on Y phone running X version of the OS because it has odd behaviour, and that happens all the time with any of the native toolkits.
That said - I haven't used Swift UI, so it's possible the situation has improved (although I wouldn't bet on it).
This is the key point where Flutter wins over both React Native but also the native Android and iOS toolkits. When you design a screen in Flutter, it will behave as you expect on every different version of Android and iOS. You just check it does the right thing as screen size changes (which is usually pretty easy to implement, and very easy to test) and then you get predictable behaviour. It is so rare that you need to fix X screen on Y phone running X version of the OS because it has odd behaviour, and that happens all the time with any of the native toolkits.
That said - I haven't used Swift UI, so it's possible the situation has improved (although I wouldn't bet on it).