TLDR: Flutter made its debut at the Game Developers Conference (GDC) in San Francisco, showcasing the progress made in building games with Flutter. Over 15,000 new mobile games have been developed using Flutter in the last year. Flutter offers advantages for 2D casual games, such as being open-source, having a rich plugin ecosystem, and supporting cross-platform deployment. The future of Flutter game development includes expanded resources, smoother deployment on various platforms, and exploration of 3D capabilities.
I’m not much active in these communities, but I think there are a few which aren’t very popular but are enough for the job… I just remember that after the Unity outrage, people were recommending moving to Godot.
Looking into their page, it gives me an impression that its doing something similar to UEFN and things like Nintendo's "game builder garage" - meaning they're trying to make game development easy by avoiding coding as a requirement.
They used trivia crack as an example, looks like it would be very good for knocking out simple games quickly - I'm thinking Facebook style games like farmville, but for any serious development or if you're looking for employable skills, you'd want to go with unity or Godot