This feature should be high on the priority list. Right now, not being able to host documentation online forced me to maintain two duplicates of the code in ARHeadsetUtil. I also had to give extensive instructions to users of ARHeadsetKit to get documentation to compile properly in Xcode, and having it already exist on GitHub pages would make much more people inclined to try (or at least skim) the tutorials. I took the entire SwiftUI course on Apple's website, not in the Xcode documentation viewer, and I suspect that other people feel the same way.
This would also allow the replacement of Google's Colab notebooks in the resurrection/successor to Swift for TensorFlow: Swift for TensorFlow Resurrection: Differentiation running on iOS