(As for me, I haven’t written one line of Haskell. Might never do.)
Another thing I believe: Most (but probably not all) projects are better off not using Haskell.
Most software is better off without C++, or Haskell, or Julia, or Nix for that matter.
But when every edge matters: one would be foolish not to reach for the sharpest knife that one can handle properly.