On the higher level question in the article of why do people not use their main languages for basic file and command management?

I believe the answer is the same as to why Python remains hugely popular despite all the well-documented shortcomings: batteries included.

Shell languages include so many neat and concise ways to execute commands, deal with their input, output and exit codes, allow simple traversal of deep directory structures with globs and advanced tools like 'find' or 'xargs', that everything else is very unergonomic.

And niche by default (until it gets used widely enough), so even your LANG-OF-CHOICE-expert you recruit, they will not know a thing about that shell-focused library in LANG-OF-CHOICE.