I believe a great reason for this change in focus is partially age, and primarily due to the extent that my days are focused on building the next great startup application. We recently (as of the New Year) pushed the past eleven months worth of work into existence as our new primary (Python/Django) product replacing the previous multiple iterations of our legacy (Java) product. The focus and scope of the project limited my ability to go off on tangents wherein I could code my personal projects freely. This was by no legal hand binding, it was simply a matter of wanting to focus my writing to building our product to the level it needs to be, to the high standards we require (and rightfully so).
This leave one (me, namely) with little actual time to thunk down in front of my primary workstation to commit theory to codebase, hence I've found myself working it out on handheld whiteboards, sketchpads, napkins, chalk on the ground whilst playing with my daughter or even simply working these theories out in my head. While I would like in many cases to put my thoughts into actual runnable logic, I've found that the exercise of stepping through theoretical code in my mind has kept me sharper regarding my thought processes. True, I cannot share this as easily with friends afar, but given that many of my personal friends are also senior level engineers, discussing (when we do) casually my theories and ideas, they get the gist quickly.
The point I'm trying to get across here is that while today is perceived as one wherein a bunch of 20 year olds either in or fresh-out-of college spend an obscene amount of hours in incubators or at startups killing themselves churning out ridiculous amounts of code, there is most definitely no slow down in the thinking processes of the more senior of us out there. We just don't find a necessity it raw churning out of code as it is the concepts that drive the field and aid in future innovation. Let those who wish to "do" continue to run their path, but lets not overlook the value of those who've moved their focus (whether by situation or by intention) to the more abstract realm of theory as the two are inextricably bound. We need ensure that these two distinct groups of people are in contact with one another because it will ultimately lead to the newer advances, bettering our field for all involved.
