I'd compare it to the ability to write and run basic assembly. We did it, and got checked on it, but that was not what we were there for.
Why? Because otherwise they’d have no idea if the answer provided to them is “correct”. As the saying goes, garbage in garbage out. You type the wrong numbers into the calculator ? How would you know the answer is also wrong unless you knew “about” what the answer should be?
The problem is that we’re letting kids go to the gym with a forklift, and we need them fit by the time they join adult life.
The kind of task is not the same. With a calculator, you are delegating a very specific, bounded, and well-defined task. Being unable to approximate non-integer square roots by hand isn't the same as not knowing what square roots mean or when they are applicable. However with LLMs, people are often (trying to) delegate their executive-function and planning.
Another way to tell that the tasks are qualitatively different is to look at what levels/kinds of errors users will tolerate. A company selling calculators that gave subtly but undeniably-wrong answers 5% of the time would rightfully go bankrupt.
If you want to compare LLMs to something of yesteryear, it's closer to hiring someone to do the work for you: That's always been considered cheating, regardless of how cheaply the accomplice works or how badly they screw up.
Look at some of the SAT math questions:
https://satsuite.collegeboard.org/media/pdf/digital-sat-samp...
The questions are all designed to have a tidy, closed-form answer. A calculator is either marginally helpful or outright cheating.
You do realize those students learn arithmetic in an environment where calculators are not allowed right?