and Ergott's new source of business!
Hey, I resemble that remark!
Seriously, carbon seat stays could be designed to account for the extra 2.5mm and still give you the heal clearance needed with the right layup. It may not look pretty, but I'm a function ultimately over form. If I wasn't I wouldn't have taken to the newer Campagnolo lever over the previous shape. They don't look better, but they are much better in my hands.
I'm quite positive that there will be a significant period of time where caliper brake road bikes will coexist with disc equipped road bikes. There are advantages to both systems. For sure I'm in no hurry to get rid of my Spooky or Ottrott. They are insanely good bikes. Companies like Trek, Specialized and Giant (the big boys) will have both options for at least a few years until the market sorts things out. If disc equipped road bikes outsell caliper braked bikes by a huge margin, that's the way things will progress. There will always be smaller companies or custom builders to cater to any market out there with the demand.