There are all kinds of technical details in software that almost no programmers understand - stuff like how their operating system's process scheduler works, or how the algorithm used by the network stack confirms that a packet was received. To have control and direction over a product, humans have always just needed to understand the details of how that product works well enough to deal with whatever can't be taken care of automatically. We will see if that still includes "the code" in a few years time. I think it will still include "the spec," in whatever level of detail that that needs to be in.

Understanding was always the bottleneck.