If there were a large number of people who didn't quite understand what it meant for a function to be continuous, let alone smooth, who were using such a calculator, I think you'd see similar issues to the ones that are identified with LLM usage: a large number of students wouldn't learn how to compute definite or indefinite integrals, and likely wouldn't have an intuitive understanding of smoothness or continuity either.

I think we don't see these problems with calculators because the "entry-level" ones don't have support for calculus-related functionality, and because people aren't taught how to arrange the problems that you need calculus to solve until after they've given some amount of calculus-related intuition. These conditions obviously aren't the case for LLMs.