The only definitive answer I've found is here: https://developer.apple.com/forums/thread/12097. But source not cited, and maybe something's changed in the intervening 8 years. I hope so, as I'd like to collect things like accuracy. Having external position paired with internal meta data seems like an odd and limiting choice.

Adding libswift_Concurrency.tbd did not work for me on Xcode 13.2 (not even RC). I was forced to go back to 13.1, which worked, and hope Apple can get it resolved soon.

While I understand Rincewind's answer, it doesn't explain why iOS 15 lost the ability to consistently find the scroll view. I have made no changes in my hierarchy, and the app still targets an older SDK, however in iOS 14 the tab bars have a proper blur background, but in iOS 15 that is just gone. This strikes me more on the order of a bug, not a feature. This occurs on every scrolling screen in my app, which means it's failing for all kinds of hierarchies. And they're not tricky, e.g. here's one: ZStack { VStack { // stuff } ScrollView(.vertical, showsIndicators: false) { // stuff } } Finally, the scrollEdgeApppearance that would fix this is not available unless you target iOS 15. Seems like a hellish catch-22.