I would be really careful about making sweeping claims about teaching programming. There are many variables at play here: your students' background, how you tea

I would be really careful about making sweeping claims about teaching programming. There are many variables at play here: your students' background, how you teach, what you teach, and so on. I doubt you have controlled for all of these. I have exactly the opposite experience teaching programming. My students grasp recursion very quickly, immutable is easy, etc. In particular, students without prior programming experience pick up these FP concepts very quickly.