I would not be surprised if a much larger volume of Clojure source code is in publicly-visible repositories. I’ve not met too many COBOL or Fortran hobbyists.
I suspect the frontier models have a more fundamental sense of programming logic and aren't limited to surface syntax. Has this been proven? I feel like the papers that have come out suggest this, but I haven't read one specifically testing it.
I'm surprised it did so poorly on COBOL.
How does it do on other esoteric languages or a newly made up one?
Re: Clojure, this test does show it performs about as well with Common Lisp as the others. I would expect it can handle other Lisps as well. They can all generally be thought of as extensions of a proto-Lisp.