That seems like a stretch. When you look at the Fuchsia OS repositories in Github and select these by language the overwhelming bulk are C++. Regarding the la

That seems like a stretch. When you look at the Fuchsia OS repositories in Github and select these by language the overwhelming bulk are C++. Regarding the languages you cite: there are some non-trivial parts in Go; the Fuchsia package manager, for instance. There are several bindings to certain key parts of the OS provided for Rust, but no actual Rust components that I can see. Python is used for some build and packaging utility type stuff. Kotlin is provided with one binding library with four whole commits. Regarding two others mentioned in wikipedia; Dart is actually more prominent than Go, Python, Rust and Kotlin combined. C has lots of binding libraries, but only a pair of boot loaders appear to be core components, plus a fortune stub.