People say this about JavaScript because to run code in a browser, it has to execute as JavaScript. As a result, there are lots of actual libraries or webapps that are written in other languages and compiled to JavaScript.
In contrast, you can do cloud computing in Java, C++, or various other languages. Go may have advantages, but compiling to Go would just be a choice.
In short, I really don't know what you meant or why you'd say it.
Google did a pretty amazing job of walking back the "replacement for C" talk and positioning Go as the language for web/micro/cluster/distribution/cloud/interconnected services.
But maybe I misinterpreted and (s)he meant Assembly.
If you ask me following is the checklist it passes:
1. Low memory footprint/good GC
2. Concurrency (goroutines) builtin
3. Great dependency (package) management
4. Compiled/closer to bare metal
5. Fast compilation
If you check other languages against the list they lack at least one of the above. If you feel any other language is better suited please tell.
I don't think this makes any sense. Javascript is the assembly language of the web because it's the only choice for the web (or more specifically, the browser). At best, any other legitimate choice will just compile to JavaScript, which is why it's thusly named. Go has no such privileged position; it's not even clear what it would mean to be the "language of choice on the cloud." You can write cloud software in any language you want, provided that the language has libraries for networking. All of the features you list are great, but none of them are exclusive to Go, nor are they required for cloud computing.
Eh... Then why are people experimenting with vendoring?
> If you check other languages against the list they lack at least one of the above. If you feel any other language is better suited please tell.
Ocaml checks all of them. So does Haskell (with stack package manager), with only the low memory requirement being challengeable since many aren't used to optimizing lazy evaluation.
Regarding the package management comment. If it is an experiment let results get in. Some people consider vendoring bad yet others find some use in it. If vendoring happens like it or not it wont make dependency management bad as a whole.