Nix-the-language is just a subset of Javascript with built-in laziness and a slightly different syntax. An absolute bog-standard and mainstream way of thinking about programs in 2025.
That said, Nix-the-language also suffers from all the same birth defects that manifest themselves in frontend development.
That must be it. The GP's comment really resonated with me, in that learning scheme felt like no task at all whereas I STILL feel uncomfortable with the nix programming language and ecosystem despite using nixOS exclusively on my personal laptop for two years and on my work machine for about half a year now. I've always fumbled over frontend / javascript development though, and avoid it as much as I can at work although I still end up working in it every year or so.
Nix only won out for me because of the mac compatibility, without which I can't really use it at work
The problem is that you're very rarely exposed to it directly. You are always multiple layers of abstractions away from it. Most of these layers are completely undocumented.
For example: https://shealevy.com/blog/2018/08/05/understanding-nixs-stri...
I've not written nix, but javascript is a ugly, terrible language. It would make sense that if nix derives from it (whyyyyyy) it would also be terrible.