To be fair, as a Rust fan I think Kotlin and Swift definitely do better in app development still. They have a lot of good language features and their communities are stellar.
I don't insist on everything being Rust. But it gets very close in many areas IMO.
I'd rather use a click listener with TS/Kotlin/Swift than be forced into idiomatic Rust's architectural workarounds.
This project made the right call, using TS for the client.