That would not run counter to the popular (whether true or not) idea that by using functional programming languages you filter for a higher quality labor pool / applicant pool.
In any case, I think the "Haskell tax" concept (where you can pay well-paid programmers less if you have a Haskell shop) is stale by now. Rust attracted away a lot of FP-ers, plus mainstream langs like C++, Java and even Typescript got smarter. Haskell's biggest problem by far is the tiny labor pool, which Mercury seems to wisely avoid.