And I think at least some of us observe this and think "I'll study a related tech field and then take a job that also uses CS - that will let me grow a wider skill set than if I just studied CS." Because it isn't too difficult to get exposed to CS basics while pursuing EE or math, etc, and a wider skill set can be a valuable thing to have - you generally have more freedom in the development of your career, more opportunities to shift around and prevent burnout/boredom, etc.

It would be interesting to build a matrix showing how degrees in each STEM field are tied to jobs in each STEM field. Because I suspect CS funnels much less into the other STEM fields than vice versa, providing a view where a CS degree is tied to a narrower line of work, and hence more at risk to future market changes.