I think I probably used my TI-89 Titanium all through undergraduate and then nearly completely shifted over to using Matlab on my computer for pretty much the duration of my PhD. I am trying to recall whether I ever needed a calculator on exams in graduate school, and I am pretty sure the answer is pretty close to no.
At the undergraduate level, I definitely wasn’t allowed to use calculators in any of my math courses. I don’t honestly remember whether I was allowed to use them in my physics courses. I remember that I definitely was allowed to use them on pretty much all of the engineering courses.
In the courses I am teaching now, I am trying to deemphasize the use of calculators. At the end of the day, in the real world, everyone will have computers or calculators to solve the numerical part of a problem, so it really doesn’t tell me much that a student can plug in numbers and get a correct answer. The real challenge (and the real point of the class) is being able to derive the equations/expressions into which those numbers need to be plugged. That tells me a lot more about what a student understands and whether they know how to set up the problems and make appropriate assumptions than just plugging and chugging on a calculator.