Visual Basic 6 (and VBScript) had
Eqv operators. No one used them. Both were removed in VB.NET; to my knowledge, no one complained.
I worked on the Visual Basic compiler team (as an intern) for a full year and never once noticed that VB even had those operators. Had I not been the guy writing the VBScript compiler, and therefore had to test their implementations, I probably would not have noticed them. If the guy on the compiler team doesn't know about the feature and doesn't use it, that tells you something about the popularity and usefulness of the feature.
You mentioned C-like languages. I can't speak to C or C++ or Java but I can speak to C#. There is a list of user-suggested features for C# literally longer than your arm. To my knowledge, no user has ever proposed such an operator to the C# team, and I've gone over that list many, many times.
Features that exist and are unused in one language, and are never requested in another are unlikely candidates to make it into modern programming languages. Particularly when there is not enough time and effort and money available in the budget to make features that people do want.