How does that work for calculus which regularly looks at the limits of functions as x approaches infinity and has very real real world applications that stem from such algorithms?
The short answer is that they deal with such things symbolically.
E.g. when you calculate the area of a plot of land do you take into account the curvature of the Earth? You have to make a bunch of compromises in the first place to even talk about what the area of a plot land means.
Math is a bunch of useful systems that we humans have devised. We tend to gravitate towards the ones that help us describe and predict things in the real world.
But there is plenty of math which doesn't do either. It's just as real as the math that does.
https://plato.stanford.edu/entries/church-turing/decision-pr...