It sounds like your professors suffer from the same problem that many math professors do. Namely lecturing to an imagined audience that is conversant with intellectual debates that the actual audience is entirely ignorant of.
In the case of math professors this results in lectures where the professor gives detailed proofs despite knowing that nobody in the class followed it, you can't dare test it, and the whole class wondered what the point was. Yet the proofs are rigorous and address points that it took mathematicians decades to figure out.
In the case of your CS profs, in the 1980s I imagine that they were coming out of an era where many computer languages did not support recursion at all because doing so was too inefficient. And therefore they focused very much on exactly how you could implement them, and what the efficiency was.
In the case of math professors this results in lectures where the professor gives detailed proofs despite knowing that nobody in the class followed it, you can't dare test it, and the whole class wondered what the point was. Yet the proofs are rigorous and address points that it took mathematicians decades to figure out.
In the case of your CS profs, in the 1980s I imagine that they were coming out of an era where many computer languages did not support recursion at all because doing so was too inefficient. And therefore they focused very much on exactly how you could implement them, and what the efficiency was.