I think you might be misunderstanding the parent comment. It sounds to me like they're arguing in favor of wrapping C GUI library when writing a GUI app in Rust, not avoiding Rust entirely. As far as I can tell, they're arguing for writing new stuff in Rust that happens to be re-using some components that aren't in Rust. I'd argue that's entirely in the spirit of Rust; kind of the whole point is that you can put a hard boundary on where the unsafety lies and make everything safe outside of that boundary. When I use a Vec or a HashMap, there's unsafe code under the hood, but it doesn't stop me from writing my own code without needing to dip into unsafe at all, and there's no fundamental reason why the same couldn't be done by wrapping Qt or Gtk on Linux or Cocoa or MacOS.