Define "really good?" I don't think I've ever had them produce a script that I didn't need to correct in some way. They can write it, that's true, but we still need to be able to read it.

Bash scripts requires "set -eu" at minimum, when written by LLM or human.

It's the only language terrible enough to make the default behavior ignore undefined variables, commands, and execution errors, and happily continue executing whatever was produced by me smashing my hands on the keyboard, until the end of the file, while returning an exit code of 0, claiming complete success.

I have seen them write massively more complex bash scripts than any normal person would ever attempt, but the failure rate is absurdly high compared to when they write sane typed languages.