My take is that office is going the way of AMC. In that I mean to say that the original idea is fading fast( watching movies or shuffling paper) What is more likely is that the majority of the sq footage gets changed into something else. The survivors will be the best space that encourages people to want to go for the "feel" Allied properties in Toronto is a great example. These are former warehouses turned into exciting event space / office environments that make you feel good, essentially the opposite of a cubicle farm.
Im 37 when I was younger it was all about downtown fancy shit, now its farm weddings and brewing our own beer. Times change and people change but I sure as hell wouldn't want to go into a high-rise office ( corner penthouse excluded of course )