Flutter is awesome! I truly believe it is a game changer for startups pushing an MVP as fast as possible.
One codebase to build apps on iOS, Android and for the web (as soon as they improve the web one to the release version) is great, and Flutter is fun to use.
The drawback could be the many states of management... But that is not a deal breaker
The state management is THE headache of Flutter IMO. There are many options now and I expect Google is following this development closely. Sooner or later they'll either endorse a solution or come up with something better.
They have endorsed solutions, but as it's still quite new it's a moving target. Originally they pushed for BLoCs, and now I think Provider is the preferred state management solution. There will probably be another one soon. At the end of the day they all work, but with different pros and cons.
Even if it's not the fotm, I'm very happy with BLoCs for global state and not shying away from using classic stateful widgets and forwarding data between screens where intermediate states are needed.
If there is something I learned from being a web dev for my entire life it's to not always jump on the latest bandwagon. It's cool when things move quickly, but you must be careful to not get motion sickness.
One codebase to build apps on iOS, Android and for the web (as soon as they improve the web one to the release version) is great, and Flutter is fun to use.
The drawback could be the many states of management... But that is not a deal breaker