I think people regularly underestimate the inertial power of established technologies. Once something gets built into a technology stack, it becomes hard to change, even when you have complete control of your stack. When it is built into the general "stack" of technology and culture at large, it becomes monumental to shift it even slightly.

Coincidentally, I believe that this will be the greatest drag on the "singularity"-- legacy systems, and the cultural atmosphere which stifles the adoption of alternatives.