Have we considered the radical option of, you know, not allowing calculators on tests? And not writing tests that rely on the use of a calculator?
If there’s any appreciable quantity of arithmetic involved, that’s a clear sign that you aren’t dealing with a “higher-level math class”.
“Lower level” math courses also should not have excessive amounts of arithmetic. What arithmetic is included should be there for the express purpose of practicing arithmetic (at which point a handheld calculator is exactly the opposite of what you want).
At any point that arithmetic isn’t the point of the problem, the arithmetic used should be designed to not be a barrier or time sink. In pretty much any possible problem requiring substantial arithmetic where calculators should be handling it instead of humans, the student should be sitting down in front of a full-sized keyboard with a more capable tool (e.g. a general-purpose programming language).
Math students at any level spending nontrivial amounts of time with handheld calculators is a huge waste of their time.
Learning to fluently navigate a handheld calculator is not an important life skill, and has little to do with mathematics.
But once you get to pure mathematics courses at the undergraduate level (i.e. beyond the service courses math departments offer to engineering and science students) there is pretty much no arithmetic.
> Learning to fluently navigate a handheld calculator is not an important life skill
It very arguably is. Contrary to what HNers seem to think, not everybody wants or is inclined to picking up Python to tally up a receipt or similar, and that's quite okay. (Sure, the handheld calculator is often now a phone, but that's a difference without much distinction)
If people want to buy $5 “scientific calculator”, a 4-function calculator with a paper tape, use a free calculator app on their phone, type their arithmetic into google, ...., that’s just fine.
These devices are simple and straight-forward, and do not need extensive practice to understand.
If schools really want to spend class time practicing computations with a portable calculation device, learning how a slide rule works is much more pedagogically valuable. At earlier ages, learning how to use a soroban or counting board is also worthwhile. These devices have no hidden parts, and learning to use them is, in itself, mathematical.
You on the other hand called _all_ handheld calculators a waste of time.
Spending nontrivial amounts of classroom time on practicing using a handheld calculator is a waste. Assigning high school students long lists of exercises where they punch numbers into calculators and then write down the answers is a waste of time and attention.