Does every language have a meaningful equivalent of "case insensitive" or does that mean we end up either creating lots of special cases or preventing certain l

Does every language have a meaningful equivalent of "case insensitive" or does that mean we end up either creating lots of special cases or preventing certain languages from being used? I'm ready to be convinced otherwise, but it seems the simplest thing to do is not try to introduce the concept of "case insensitivity".