I appreciate the amount of analysis and work this took, but I don't think I'd recommend using the library.

First, it's really something that Apple should create and provide and, frankly, I'd expect them to do so at some point.

But the larger issue comes down to the fact that you're making inferences based on the way SwiftUI works internally today. And there's no guarantee that it's going to stay that way.

In fact, one only needs to look and see how List went from being backed by table views to collection views to see that Apple is still tinkering with SwiftUI and its internals.

Impressive work, though.