And learning CS to write programs is like learning to design combustion engines to drive a car.

Sometimes.

But often people will “write programs” without a decent understanding of the underlying layers and principles or foundation on which the technology is built. (Even some CS majors will do this.) this will result in weird bugs and behaviors they cannot understand or debug. Meanwhile their peers and managers have begun to use and rely on these programs and even integrate them into larger processes and workflows. Once the bugs start showing up, now you’ve got a big problem.