That extension doesn't follow. It is possible to verify if software works without knowing how it works internally. This is true with many things. You don't need to know how a plane/car/elevator works to know that it works when you use it.

I would actually argue that only a small percentage of programmers know what happens in code on an instruction level, and near none on a micro-op or register level. Vibe-coding is just one more level of abstraction. The new "code" are the instructions to your LLM.