It's a very common logic operator across a multitude of languages. In what situation do you have that sequence of characters that isn't a logic operator?
Having a ligature for != but not for the others betrays its language-independent semantics.
!= in Matlab is not legal logic operator.
Also, != might be part of regular expression.
Using Haskell is one such situation. Haskell's inequality operator is /= which someone could expect when they see ≠. Some people redefine != as a custom operator (see link), which can bring even more confusion with this ligatures.