Currently I am working on a GTK+/GStreamer desktop client program. Initially in C++ then I switched to D – D is a much nicer programming language than C++ and the GTK and GStreamer bindings are better. Then the GStreamer people decided Rust was the language of future working so I switched to Rust. Very different to C++, and better. D and Rust are just very different, both have pluses and minuses. The Rust bindings to GTK and GStreamer are good, and they have some futures/channels/executor extensions that make event loop programming nice.
When I look for GTK and GStreamer binding for Kotlin/Native there isn’t anything that gets close to what is available in D and Rust. So no matter how nice the Kotlin language is, Kotlin/Native cannot currently compete with D or Rust in the GTK and GStreamer applications arena.