They don't only work for ASCII. While the majority of writing systems in this world do not have case distinction, some that are widely used do. And arguably it

They don't only work for ASCII. While the majority of writing systems in this world do not have case distinction, some that are widely used do. And arguably it is easier for the user to understand. The people who do trip over it are mostly programmers with the wrong assumptions about how things work and then complaining that things can't ever be simple ...