Not really true, you are likely comparing a debug build. An Android Flutter apk sits around 4MB for smallest app. Most of my apk sizes are around 8MB-10MB w/ Flutter

I haven't written any myself, going from reports online that builds are a lot larger than expected. That minimum size is for an app without any components or other modules. The RN app I mentioned was ~6MB with a fully blown app, state management, heavy data layer, hundreds of components, animation, i18n, a handful of native modules, encryption, and so on.

In short, Flutter doesn't really have any advantage in size over RN.

Flutter has had a lot of performance improvements since that date. It'd be great to see that updated compared to current version

I think the Gallery in Google play is outdated, better check the one from the repository to see the current performance

This is a great article! very excited to what we will see at Dart Developer Summit 2015