Edit: didn’t exist at the time!

Python is my go-to because I know the ecosystem well and can go from zero to done with minimal effort and research.

Node has since (come into existence) and matured, and while it may be better/faster in some situations now, I haven’t encountered a project that has compelled me to switch.

I suspect the answer to your question boils down to a combination of: familiarity, preference, individual productivity, and pragmatism.

This will likely shift over time.