> the truth is that once you get to the point of "competent developer" and the meaty part of the bell curve, we are all pretty much interchangeable. It then becomes a question of who will do the same work for less.

This under-values domain knowledge and especially company-specific knowledge. Yes, someone can ramp up on a code base over time, but I don't know if you've seen how ugly the limiting case is where they utterly replace all the devs with a new set who know nothing about the codebase and drop all the organizational knowledge. The rate at which things get done suddenly becomes a fraction of what it was before and the defects multiply quickly.