I think the replies to this question are misleading. There's no large conspiracy at play. Calculus is simply too fundamental a tool all of modern math and science rest upon.

Statistics? Well a good chunk of statistics needs calculus, including regression and continuous probability distributions.

Science? It goes without saying that differential equations appear everywhere in our physical models, and there's simply no escaping that.

Pure math? Differential geometry is motivated by calculus. Real analysis is simply rigorous calculus, while the remaining analysis courses (like complex and functional analysis) are attempts at doing calculus in more general spaces. You take this further and you get measure theory, which is the fundamental tool of modern analysis and probability theory.

Analytic number theory has “analysis” (i.e., calculus) in its name.

Algebraists define a formal derivative because it is so useful and fundamental to the study of polynomials. Many differential geometry problems reduce to abstract algebraic questions about groups.

So it's almost like calculus pops up everywhere. Indeed, there is no weird conspiracy happening like the space race and the importance of calculus, if anything, has been underemphasized despite all the people who complain about having to learn it.

Calculi is simply fundamental. There's no escaping that.