Why is building a UI in Rust so hard?

This is a very informative article with some excellent points. Indeed, having worked a little in the UI toolkit realm, I agree that a different UI Component model is warranted for an efficient Rust UI toolkit.

Perhaps some of Bevy "ECS" model, where UI node becomes barebone UI entities, and everything is composed by type.

Anyway, not an easy one to crack, but I hope that one day we will get an awesome cross-device native UI a toolkit in pure Rust.