This Settings page is still using UWP/XAML though these days the more accurate term is probably WinUI3 XAML. It isn't using a WebView at all. It is using JS as

This Settings page is still using UWP/XAML though these days the more accurate term is probably WinUI3 XAML. It isn't using a WebView at all. It is using JS as the programming language responding to/driving the UI, but it's still "native controls" (in so much as such a concept ever really has any meaning).