Shout out to Dioxus. It's a react clone that provides a really nice experience and can run a web GUI faster than React can. That's quite the accomplishment given the disadvantage of having to use shims to access the DOM.
If you want to choose a single language that can create native GUI's, Rust is probably your best or only choice. Other languages are lacking a good story for either the web or for iOS but Rust works well on both.
Incremental compile times were quite fast, I'd say in the 1-2 seconds. I also have another project where I'm using Dioxus-web for a web application. When building a web app, it also has hot code reloading and I'd say reloads take under a second (though I just started this app so it only has a couple hundred lines of code).
I have an M1 Pro Max though, which is quite a fast machine.
My comment said that rust had a great cross-platform story, not Dioxus. If I was doing cross-platform rust I'd use cacao for iOS, Dioxus for web front end, et cetera.
True. I forgot about the family of languages that will transpile to Javascript. That gives most of them a good web front end story, and of course Kotlin has a good iOS story.
If you want to choose a single language that can create native GUI's, Rust is probably your best or only choice. Other languages are lacking a good story for either the web or for iOS but Rust works well on both.