Some complicated development tasks require 100% uninterrupted concentration for several minutes at a time. You're sitting there trying to build and maintain an extremely complicated model in your head, involving many complex parts, and their interactions along a time line, introducing permutations of that model to simulate the changes you are considering and simulating the outcome in your head. Then someone asks you something, or asks someone else something, or simply passes in your peripheral vision, and poof it's gone.

There a many tasks that don't require that kind of concentration, and many jobs, even in software development, that never involve those kinds of tasks. But with a setup that encourages 'communication', in the form of forced non-stop interaction, you have effectively made sure that the developers will never reach those heights, and most likely not by conscious decision, but out of ignorance.