The laws of nature that physicists actually use, however, are written in the language of Calculus. And understanding the laws in Calculus form is ridiculously useful.

Not compared with stats and other discrete maths. I studied calculus at college and university - and it was definitely one of the more useless things I learned. It's main use has been teaching it to other people so they can get through their own calculus maths exams.

Hell, everyone shouldn't just have to take Calculus, they should have to take Differential Equations as well. You cannot understand reality without calculus knowledge, or without an understanding of differential equations.

Really? Understanding reality arguably requires understanding the notion of differential equations, but understanding under what precise conditions solutions to differential equations exist, or techniques which can solve particular differential equations, doesn't really seem critical to someone who doesn't actually need to solve them.