JavaScript isn't the only programming language around. I'm not the strongest around with JS either but I can figure it out as necessary -- knowing C/C++/Java/whatever means you can still grok "this looks better than that" for most cases.

Yep. I have plenty of experience in languages that use C-style syntax, enough to easily understand code written in other languages that occur nearby in the syntactical family tree. I'm not steeped in JS enough to know the weird gotchas of the type system, or know the standard library well, etc. But I can read the code fine.

If I'd asked an AI coding tool to write something up for me in Haskell, I would have no idea if it had done a good job.

I don't think so. Imagine it was vice versa, someone saying they knew JS and were weak at C/C++/Java.