mt, you got it; I like a flexible screen, can live without it, but not happily.
As I said, it is my opinion, and we have yours - and I am really pleased that you are happy without it.
I am not putting my opinion up against that of anyone at Pentax, they get to decide, thus will "win" no matter what.
Given the multitude of physical characteristics(size-wise) of Pentax users/owners and prospective customers, worrying about or changing "under a millimeter" is just close to being silly!
I suppose for the few percent of the population that the camera is actually physically optimised for, it is great.
That said, the ergonomics are a compromise for everyone else, as is each of the other attributes and features of the camera. Some like them - some don't.
I believe that may in fact be why Pentax offer several models at any given time, and change them periodically.