I agree with you. The iOS aesthetic, though imperfect, was stable and quite nice. In my opinion, Apple should have merely eliminated some of the more egregious skeuomorphisms and brought their apps more in line with the semi-flat look that the OS has had for years. This sort of total visual upheaval is superfluous, if not detrimental. From what I've seen, it looks insultingly bad.

There are better ways to allocate development time than reimplementing an already-fine OS.