Pro users of yesteryear’s products, the people with the biggest investment in old technologies, are not the people who should be calling the shots in the design of their successors. These are the people who complain that an iPad can’t have third party software installed from anywhere but the App Store, ignoring the massive convenience and security gains the policy affords average users. These are the people who are still using slotted screwdrivers and Edison light fixtures and manual transmission cars.
As a power user, I have yet to hear a super-compelling argument as to why I need third party apps on the iPad. But I love my Edison light fixtures. Chris's main point is on Facebook messaging and email, and the same thing stands. Since Gmail, I haven't used email like I did in days gone by. I don't filter or file, I thread and search. What this process costs me in microseconds per transaction is made up in spades by freeing me from the silly frustration of keeping my email folders organized. (Taking the time to learn how search really works is the single biggest process gain one can make in streamlining the day-to-day buckle-shuffle of email.) Once I made that liberating cognitive leap, de-evolution of messaging as is on display in Facebook is a lot easier to understand.