Short answer: (language) sampling bias.

Because almost no entry-level programmers are coming in with clojure.

Same goes for F# and Elixir.

Most folks in these three languages have a lot of experience under their belt, and so they can get commensurate pay.

According to the State of Clojure 2021 survey https://www.surveymonkey.com/results/SM-S2L8NR6K9/

There is an fairly even distribution of YOE with 25% having 0-5 YOE

do you expect javascript, python, java, and C# to have 25% 0-5 YOE?

As a guess: small communities simply have larger variances, and we only notice the high-paying ones. (Same principle as when there's maps of rates-by-county of something or other in the US and all those empty counties in the west stand out for being super high or super low).

I like to think of it as "the law of small numbers"

Normalize the data by years of development experience and country of origin.

exactly. data is pointless by itsefl

Is there any big corp using it massively? why the shift up? It's kind of curious that a lisp is at the top of the list (according to SO). Not surprising, but curious. What do you think? any ideas?

This link answers your questions about companies using Clojure.

https://clojure.org/news/2021/04/06/state-of-clojure-2021

(700 Clojure devs at the biggest shop, Nubank.) Although I would be surprised if their salaries were at the top of global developers.

Especially considering Nubank is Brazilian, and even though they pay well for Brazil I doubt it gets close to US standards

~3k to ~5k dollars a month, no vesting, and I'm not sure if there's a bonus structure. At least 22% of the Clojure workfoce make entry-level money by US standards, so the other 78% must be doing pretty good

Geographic distribution of developers and relatively low amount of devs? If most Clojure devs are in the US (where generally the highest dev salaries are), whereas for other languages they are more spread out around the world, then Clojure will be at the top even if it isn't necessarily the top paying programming language in the US itself (no idea about that).

Fewer companies use Clojure, while Clojure attracts talented, experienced programmers. This community of Clojure developers paired with few opportunities creates higher demand and thus higher pay

Walmart has a decent amount of Clojure

https://clojure.org/community/success_stories

Another, less kind answer: it was the flavor of the month about a dozen years ago, some devs decided to build everything in Clojure, now the software that runs entire large companies is in Clojure, nobody knows how to maintain it, so the only ones left over take large salaries. It's kind of like COBOL in banks, except it was hype driven and not we-had-no-other-option-at-the-time driven.