This seems to me to have a serious architectural issue. If I read it right, the app is rendered in the browser but is processing state changes and doing HTML rendering of the state tree on the server side? How is that going to scale?

This is a really neat adaptation of the SwiftUI API to the web but it seems like the guts of it needs to run in the browser to be practical.

Perhaps we'll eventually see the Swift compiler support a WASM target?

[edit] Like Qt is doing? https://doc.qt.io/qt-5/wasm.html