Use case

Flutter create automatically creates a pure-white launch background for Android (in android\app\src\main\res\drawable\launch_background.xml, with a @android:color/white drawable).

Proposal

Instead, it could use the ?android:attr/colorBackground theme attribute to have a launch background that depends on the current light or dark theme.

cf https://developer.android.com/guide/topics/ui/look-and-feel/darktheme#launch_screens