I can't speak to rust but I think the reason you see CLI tools and Servers written in GO is simply because that is where the language really shines. I don't think it would be very much fun to develop a desktop GUI app in GO.

Go is kind of verbose and just a bit hostile towards fancy structural features and complex abstractions. I think rust is kind of the opposite of GO in a lot of ways, even though they theoretically should be targeting a lot of the same use-cases.