In reality a $5 “scientific calculator” (or a slide rule) works for 99% of use cases (high school math homework/exams). The only thing I know of which strictly needs the TI calculator is the AP calculus test. Students should just borrow a calculator a few times to prepare and then for a few hours for this single test. Getting them to spend $100 each to keep the calculator is a total racket.
Better still would be to eliminate the need for a TI calculator from the AP exam, and then there would be no need for it whatsoever.