There's good reasons to having a dedicated, more limited device.

What bothers me is that the device is a hard requirement for students, which means TI and Casio get to charge unreasonable amounts of money for these calculators that are not reflective of what they'd otherwise be worth. I brought up the Chromebook not so much as a suggested alternative, but as a benchmark for what sort of hardware you can get for the same money when your market isn't completely tied to your product.