Funny enough, I use Python primarily, but when it comes to deploying small standalone tools I have a list of things I want to rewrite into something like Go so I don't have to deal with dependencies. In my little experience with Node it seems even worse. One petty but relevant fact is that Node isn't installed by default while Python generally is.

I can definitely see prototyping something in whatever language is convenient and after proving its usefulness rewrite it in a language that fits wider goals. Their motivation[1] seems pretty solid.

[1] https://github.com/Azure/azure-cli/wiki/Motivation