When the TextInputEditText.Hint attribute is established in XML, the label animation works just fine when you start typing in the field.
When the TextInputEditText.Hint attribute is established in code, the label animation doesn't work.
I don't mind using XML for the hint, but our localized strings are up in a shared Xamarin project, and it seems there's no way in Xamarin.Android to use XML data bindings to point the Android XML at my LocalizedStrings class.
The app is targeting Android 9.0 and using Xamarin.Android Nuget packages 28.0.0.1.