Learning how to program, especially when one doesn't come about it through self-selected autodidactism, can often seem to be an insurmountable challenge to people who don't know how.
This applies to even extremely technical, highly intelligent people. Often they recognize that there's an extraordinary time component to learning, and they optimize around that in other ways.
Learning to program is a weird thing because once you learn the mental processes of how to do it, it comes fairly easily. But the idea of "I'd like a tool that makes websites for me" and then knowing how to divide that problem down to the right mental abstraction model that perfectly (or near perfectly fits) some programming language and technical environment is a very difficult learning curve.
It's much simpler then to present small technical pieces that are well constrained in scope and definition and have tooling somebody else built do all the rest of the heavy lifting.
Static site generators are one of those things that are relatively easy, even for newish programmers, to build, but exist right on the other side of that learning curve for non-programmers.