This was my workaround in my subclass of UserWidget:
void UMyUserWidget::NativeOnInitialized()
{
if (!HasAnyFlags(RF_ClassDefaultObject))
{
if (auto* CDO = GetClass()->GetDefaultObject<UUserWidget>())
{
bAutomaticallyRegisterInputOnConstruction = CDO->bAutomaticallyRegisterInputOnConstruction;
}
}
Super::NativeOnInitialized();
}