More generally what you're referring to as elitism is really just the result of a simple theorem. As the size of the set of Xlang programmers approaches the size of the set of all programmers, the average competence of an Xlang programmer approaches the average competence of all programmers. The asymmetry is that, as far as I'm aware, there aren't really any significant languages that attract small communities of abnormally incompetent programmers. On the other hand, there are languages, like Haskell, the MLs, and some Lisps, that do attract relatively small communities of abnormally competent programmers.
None of this is to say that someone that only writes JavaScript can't be an exceptionally competent programmer. We're talking about group averages here.
There's also survivorship bias in sticking long enough with programming to actually look for jobs in niche languages or accept that you will be taught on the job, something that I've seen only with either experienced or more open-minded/educated people
Counterintuitive, it was the "elitist" lower numbers involved in some languages (not just Lisp) that were found to be advantageous by some companies in hiring. Essentially, it selected out people with lower experience and those not willing to learn a new language. An example I was given was that choosing Common Lisp and combining it with globally remote hiring greatly increased the quality of incoming applicants - and that had they went with the popular option (Python in their case) they'd have to deal with deluge of fresh bootcamp grads of which many had unwarranted high opinion of themselves.
Both Kina Knowledge and ITA Software (and from what I heard but can't cite now, other companies as well), teaching people Common Lisp on the job apparently tends to work pretty well, and willingness to master a new language correlates much better with good skills. It does have the disadvantage of not being able to throw a new hire directly tickets to solve, but the timeframes I was given were essentially "it takes around a month for new hire to go from zero to productive lisp programmer".