On the other hand, calculus prerequisites are a filter that filters out anyone who might be inclined to say "math is hard" and give up, which might correlate with people who say "computers are hard" and give up. Or in other words, it's easier to say "Prerequisite: Calculus 2" than it is to say "Prerequisite: be sufficiently determined to complete something many people find hard and give up on, or be one of the people who found it easy to begin with". And lo and behold, rather than getting people taking an advanced CS class and giving up, you instead get people not taking the class in the first place because they don't meet the prerequisites, which makes numbers look a lot better.
This is not the best solution for the problem. It's the solution most CS programs take, though.
(Necessary disclaimer because internet discourse: this is a comment on CS education in general, not a comment on Lambda School in any aspect.)
I think the issue is that many programs expect students to understand 'the basics' of calculus as an academic mathematician understands them, which I would consider to be more suitable as an upper level elective for a CS program.
A fun exercise would be to have graduating CS students take the same calculus exams that were required for admission to the program. I would expect that 10% would score much higher and the other 90% would score much lower.
Spending too long in STEM academics absolutely warps your view of the mathematical skill floor I think.
Use it or lose it.
I’m sure chain rule, product rule, and polynomials would come right back to you, and everyone has to look up the trig functions anyway.