> Packaging for nix is exceptionally easy once you learn it

Most of the complaints I've seen about Nix about around documentation, so "once you learn it" might be the larger issue.

I don't in ow if I'd say it's "easy". The Python ecosystem in particular is quite hard to get working in a hermetic way (Nix or otherwise). Multiple attempts at getting Python easy to package with Nix have come and gone over the years.