Have you ever put a lot of work into defining loads, connections and constraints on a model for a static stress simulation and then wanted to do a modal analysis on it? You'll spend quite a bit of time redoing the same definitions again, because there is no option to copy loads and constraints.
So, my proposal is that if you select to duplicate a study, give the option to switch to another study type. Sure, not all types of loads and constraints are available in all study types but at least duplicate those which are relevant. Or alternatively, make it possible to copy/paste.