if you know the consequences you can write your own orphan-instances for Functor etc.
but be warned that they may explode in your face if the optimizer looks at them wrong as @f-a has already posted.
But most of the time you want to use mapMonotonic anyway as it is O(n) instead of O(n*log(n)).
Your call - but in any case there should be no “default”, because there is no unique emphasized text"correct" instance.