I can see it working for an opposite reason. Someone who has been paid decently to write mathematically challenging software in an interesting and ergonomic language would probably want a premium to go somewhere they use a boring annoying language to solve lots of trivial problems. It is an extension of why game dev and to a lesser extent, embedded dev, pay less than full stack even if they are typically more challenging.

Many years ago, I interviewed with Jane Street. They asked me C++ questions and if I am willing to learn OCaml. Sure, I can learn any language. The position was given to someone else who already knew OCaml. They use OCaml for everything, building software to distributing it etc. That's my interview experience with them. I think they chose that language because it can be as speedy as C++ with proper knowledge and optimizations. I do not know OCaml besides learning it when I worked with researchers/mathematicians who wrote OCaml and i had to understand the code.