Flutter doesn't use native controls/frameworks under the hood, so it generally falls into the category of "trying to shoehorn in a single look and feel everywhere".

It enables a lot more customization and complex effects precisely because it draws every pixel itself.

Thats not necessarily to its benefit.

Not necessarily bad either - some companies may want distinct experience in their app across all platforms l. Any UI is fine as long as it is fast and efficient.

It is to the benefit of the developer and the user that they're able to have better UI.

Yes, precisely. It has a "Cupertino" theme that kind of mimics the iOS look and feel, but it misses the mark and will always be behind the curve a least a release or two in matching the OS.

OK I misunderstood your ask then. In that case Xamarin.Forms does that today