I was actually thinking about how much work it would be to rewrite the backend of Node-RED in python. Such as, serve the same front-end through Flask instead of express, interpret the flow.json with python and instead of nodes having an "html" and "js" file you'd have an "html" and "py" file. Then you know, just write a wrapper for each module in the entire pip library.
The actual "language" itself doesn't matter, but these pre-written modules have semantics that their users had to learn. To me, this is the strength of NR as the semantics of your familiar NPM modules don't change, just the interface with which you do it has changed. It only makes sense that python users would feel left out 
