It makes sense that KHAN would be the one to get the best treatment given how the process is expensive. As you said, only reserved for a small number of movies, usually the classics. RoboCop will get 4K restoration, but none of the sequels ever will. That doesn't mean the other films couldn't have gotten an impressive transfer without a 4K restoration, as the latter James Bond and Indiana Jones films showed. It's just a shame Paramount went with the more cheaper approach by applying the DNR and calling it a day.