I understand your point, but I would say that it is not particularly appropriate for a teacher to use AI (or plagiarize, to an extent) in this context. Taking questions from an existing bank, in my opinion, is different to AI generating your prompt/email/etc. What I mean is, students will NOT listen even more so if they find out how blatantly hypocritical a teacher is being (in the hypothetical situation that the teacher really did use AI)

This isn't a made up situation. Teachers at my school have used AI for essay prompts, test questions, etc and it spreads around and generally leads to the sentiment that "if the teacher is doing it, they can't in good faith tell me to not". Imagine if in math class the teacher , after just telling the students they can't use a calculator, types in a simple arithmetic expression into their calculator.