I'd like to see a more detailed comparison
One of the differences between CS and the pure sciences is that if you want to put on a science or hard engineering course you will need expensive labs, associated technicians, and supplies. Any institution with a computer room can run a CS course.
This shows. I recently interviewed a grad who had done a CS-lite course at one of the low tier universities, and the poor kid could barely code, with huge gaps in his knowledge. I really felt sorry for him, as far as I'm concerned he was ripped off. I could code better before I went to university than he could after three years.
I would like to see a comparison of employability of CS grads taking into account the institutions they come from. I suspect we might see the difference narrow when you just include the better institutions.
The comparison with the other STEM subjects is also instructive regarding what CS courses don't teach, which is the practical craft of programming. If you do a science or hard engineering degree you will be taught how to conduct experiments, record your results, keeps notes, how to use the lab equipment, how to actually do the practical side of your subject as well as the theory. These things are taught all through your course. When you graduate you would at least expect to have enough skills to get you started in a commercial lab.
The equivalent skills in CS, like how to use source/version control, test your code, work in team environments, document your code properly (not an academic project writeup), these seem to be rarely taught in CS courses, and if they are they are done as a one off, when they need to be woven into the entire course (e.g. submitting coursework through the source control system, with complete version history and test set).