There is (among others) a specific reason that HR departments have come to demand a degree: labor regulations under Fair Labor Standards Act, that set the criteria for exempt vs. non-exempt positions. Regulations have evolved so that a gating criterion for an engineering or technical occupation, to qualify as exempt, is an engineering or science degree.
One division of the regulations provides an exception for computer-related occupations. One reading of this appears to exempt most programmers from the degree requirement, but I have heard of conflicting interpretations (e.g. this exemption is intended to apply to IT work, but not to more engineer-like embedded systems work).
The alternative is the learned professional exemption. The criteria here appear to allow some latitude, but the black letter statement is that a degree in one of the sciences, engineering, theology (!), etc. qualifies a person under this exemption.
As FLSA regulations evolved, a number of companies went through job reclassifications, taking non-degreed exempt engineers to non-exempt technician titles.
I was an embedded systems developer, no degree, for 30+ years. My company shut the division that I worked for. I went back to university for a degree in physics, because I wanted something intellectually disparate from my field of work. I qualify under FLSA, but perhaps an HR department would still discount my degree as not being in CS. That said, I went back into embedded systems immediately after graduating.
As a returned adult student, I had the opportunity to observe the university as well as to attend it. There are several reasons that students are taking closer to 5 years to graduate. First, uneven preparation coming from high school. Second, a more liberal policy toward retaking failed or D-grade courses than existed in in the early 1970s. Third, especially after the economic shock of 2008+, a positive surge in enrollment coinciding with a negative surge in funding. It can be difficult to get a seat in required courses. This can turn a 1-semester wait for a course, into a 3-semester delay in degree progress.
Evidence on preparation gaps: 40% of the seats in my first semester main-sequence freshman chemistry class, went to students who dropped or failed the class. The most frequent deficiency was in basic high school algebra skills. Second might have been too much attention to alcohol and modern high-THC weed. Make that third; I think second was rapt attention to text messaging rather than to the lecture. One aspect of being a returned adult student who is doing the work, is being pulled aside to hear the professors' woes; that is where I got the 40% number.