Your argument is nonsense and can be extended to: he didn't even mention the servers, be sure to add a few megs of RAM for each feature to developed, and some HDD space too. Oh, and increase the chip speed for each new feature as well! Then later but new servers to replace the cobbled together disasters you built on the fly.
We use Agile for the *development* process which is distinct from the *design* process. That is, we do architecture up front, including DB design, and - surprise - we even build the server platforms too!
Business gets an opportunity once a month to change development priority order. Once. A. month. New features introduce are written up, added to the feature list and the business gets to include them in next months re-prioritization.
It's simple , everyone gets it, and the business (ie the people paying the bills) love it. And that's bad, how?