Flutter is only in beta for desktop and web. And it's emulated UI, not true native UI.

RN is ready now and today for all platforms, including Window via react-native-windows.

Microsoft is choosing React, I wouldn't go w/ Flutter.

Why would you choose a Google only language and framework... unless you like rewriting code when it dies.

Also, w/ React you can use TypeScript or JS, you don't have to learn a new language.

From my perspective, it looks like Google pays a lot of money for these tech articles and stars, it's not a really good way to look at things. There's always a Flutter campaign going on.