It doesn’t have a qwerty keyboard. That would be such a pain to type on.

For some reason qwerty keyboard calculators are banned in tests.

I think those were aimed at different market segments. And that would be engineers, professionals and working academics that is not students.

Generally limitations in education on what was allowed led to more limited feature sets. Where as full feature set that could be upsold with qwerty keyboard was aimed for different users.