I'd say there is a conflict of visions (or values) at work here, and I have no idea for a better way to resolve it. Maybe someday, there will be a layering of features so, at the bottom there is simplicity, and at the top, a huge menu of choices to nicely fit every situation. Both @Slava_Pestov and @Douglas_Gregor have done this with rewriting major portions of the implementation, and I'm sure others have, too. So some times, things get simpler at some levels. Sigh, every improvement takes time and money, exacting an opportunity cost.
Crazy idea: What would happen of the users of Swift funded the development of Swift? (at least partly) But Swift needs to serve Apple's needs. And academic languages must serve the needs of granting agencies. Beats me, Batman!