I'm not a Go user but I agree. While I make Node CLIs for myself because I'm very quick with JavaScript, I'd choose Go if I was making something for a lot of people!
Go has been a game changer for me also. There is also a very good package https://github.com/spf13/cobra that can make the development of complex CLIs easier.
Go default flag package is pure garbage though. That's a fact. However, Go cross compilation makes it easy to develop multi-os CLI tools. The downside is the size of the executable, it's easy to reach the 50MB bar with Go binaries.
Yes. The default "flag" package is trash. I like the Go team a lot, and I think they did a great job with many things, but it seems to me like they just said, "meh, get something that can work, usability is not something that matters."
consider the history, it probably makes sense if you're used to research unix and plan9
Using something like Golang for distributing compiled binaries means that as long as they have the CLI, it will continue to work. With Ruby, Python, PHP, etc, there is absolutely no guarantee that your application will work in the future.