Data Trigger Not Working

Hello,

I am going through the XAM320 - Design an MVVM ViewModel in Xamarin.Forms course in Xamarin university which is unfortunately going away end of this month. I am going through the first exercise and the data trigger example is not working. Even the completed course (answer code) they gave is not working as well. Are Data Triggers not working at all?

Here is the code from github from the instructors :
https://github.com/XamarinUniversity/XAM320/tree/master/Exercise 1/Completed

This specific code is not working:
<Label Grid.Row="1" Text="{Binding Author}" TextColor="Blue" HorizontalOptions="End" HorizontalTextAlignment="End">
<Label.Triggers>
<DataTrigger TargetType="Label" Binding="{Binding Gender}" Value="Female">
<Setter Property="TextColor" Value="Pink" />
</DataTrigger>
</Label.Triggers>
</Label>