Linking Assemblies leads to Binding Property not updating

In my Xamarin.Forms app, there is an issue when creating the Release build:

In MyView.xaml, I have a Label with a Text binding:

<Label Text="{Binding ProgressInfo.Message, Mode=TwoWay}" />

In MyViewModel.cs I have the Property:

private (double Value, string Message) progressInfo;
public ( double TotalProgressInPct, string Message) ProgressInfo { get => progressInfo; set => SetProperty(ref progressInfo, value); }

where SetProperty is from a different assembly (MvvmHelpers)

The update of the text label works fine with No Linking, but not with Link SDK Assemblies, where the Label text does not update. All other Labels are updated just fine.

For some reason, the tuple character of the property does not work nice with the Linker? Thankful for any hints!