In this discussion I've been trying to make the point that he's missed the mark even in the idea that developer attitude is the inherent barrier preventing these breakthroughs. I believe he's stealing bases here. At least with respect to visual programming, there is objective evidence (that is easily google-able) that this problem is actively being tackled but with very little success. Active and recently failed projects seem to be glaring counterexamples to his broader point, at least with respect to the visual programming domain.

I suspect that my point about presuming developer attitudes are the biggest problems here can more broadly applied though I do not have enough experience with constraint-based solvers and his other examples to do more than wildly speculate.