Can someone please explain why the fact that it was in Node and is now in Python matters in the slightest, given that it's a command line utility that doesn't seem to, in any way, expose the language it is written in?

This could be in haskell or F# and it still wouldn't matter because it's the CLI itself that matters. (to which the question must be: is Azure popular? Is a new version of the CLI utility big news?)