SwiftUI iOS 14/15 Can't tap Button underneath Spacer in ScrollView

Question

In SwiftUI, I have a Button that's underneath the Spacer within a ScrollView. The ScrollView steals the tap gesture, so the Button never sees the tap.

So, for example, the button in this example does not work:

struct DoesNotWork: View {
    var body: some View {
        ZStack {
            VStack {
                // Button doesn't work
                Button("Tap This") { 
                    print("Tapped")
                }
                Spacer()
            }
            VStack {
                ScrollView {
                    Spacer()
                        .frame(height: 150)
                    Rectangle()
                        .foregroundColor(.blue)
                        .frame(height: 150)
                    Spacer()
                }
            }
        }
    }
}

This version -- with everything else the same except no ScrollView -- works fine:

struct ThisWorks: View {
    var body: some View {
        ZStack {
            VStack {
                // Button works normally
                Button("Tap This") { 
                    print("Tapped")
                }
                Spacer()
            }
            VStack {
                Spacer()
                    .frame(height: 150)
                Rectangle()
                    .foregroundColor(.blue)
                    .frame(height: 150)
                Spacer()
            }
        }
    }
}

So that rules out the VStack, ZStack, and the Spacer.

I've tried using .allowsHitTesting(false) on the Spacer that's within the ScrollView, and also tried .disabled(true) (and in combination). Adding .allowsHitTesting(false) to the ScrollView makes the button works but of course breaks the ScrollView.

I also tried setting .foregroundColor(.clear) on the Spacer.

For what it's worth, I'm having the same behavior with both Xcode 13.0 Beta 5 testing with iOS 15.0 beta 7, as well as with Xcode 12.5.1 with iOS 14.7.1.

I'm out of ideas. It seems like it should be the simplest thing in the world, but I can't figure out a way around this.

Any help is greatly appreciated!