There are many questions (including one of my own) that fall into the category of "Why did X company do Y?" Should these questions be removed for not being constructive? Examples: iOS multitasking closing is poorly designed? Why does MS Outlook Express store data in a hidden folder? Why are nested elements scrolled to the opposite direction? What reason could Nintendo have had for putting the A and B buttons the wrong way round? What is the reason for Concave round buttons in Elevators What is the reason behind the + sign/icons with buttons? What is the reasoning behind grayscale icons?
That's just a few of a MASSIVE population of such questions.
I think what needs to be determined is: Is UX only a place for people to ask questions about prospective/existing designs, or does UX also foster discussion about famous/classical design implementations/commonalities.