I posted a link to a copy of the text of the law in question. Maybe it's an inaccurate copy. Maybe it was repealed before it came into force. Maybe the translation is even more broken than it appears. Yet if so, it ought to be easy for the people that are so insistent that it was never illegal to find documentation, such as the real text of the law, a better translation, or documentation of its repeal. Yet none of that appears to be forthcoming, just a stream of examples of recent usage of the letters from after Turkish society started reforming, 50-60 years or so after the law in question was passed.
It's great if the problem has been rectified. But that is far away from claiming it never existed in the first place.