Because rust is a lot harder to experiment with and really does not work for interactive or notebook stuff. Python also has a massive ecosystem of existing libraries.

And thus rust is used to either make tools, or build libraries (de novo or out of rust libraries), which plays to both strengths.

It would be a wholesale move from one of the easiest programming languages to start on, to one of the hardest languages to start on.

Most programmers I've met were beginners, and they need something easier to work with until they can juggle harder concepts easily.