I know there is no flag library built-in in rust (I do quite a lot of rust as well as go). That's my whole point. It should be compared to something like https://github.com/urfave/cli . That would be a fairer comparison.
Sure, for example I usually use Cobra. But what I meant was that people often mention Go as being explicitly preferable to Rust for CLIs, and I’m not sure why if I have to pull in a dependency in either case.