Cannot Preview SwiftUI - dependent package

I have a normal UIKit project with a package dependency containing some SwiftUI. Opening the package on its own, I can preview the SwiftUI. However, when I have the package as a dependency, I get the dreaded message saying Active scheme does not build this file regardless of choosing the app or package scheme.

Why can't I get a preview?

Using Xcode 16

Cannot Preview SwiftUI - dependent package
 
 
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