sorry you had this experience. School should be a safe environment. When intimidation is used, it could be just as detrimental to the learning process as any learning disability.
Just be careful not to paint with a broad brush. Not all adults are like that, and not all teachers either. When I taught school and a significant number of students failed a test, then that told me that I did not cover the material well enough. Formal assessment is as much for the teacher as the student. It sounds like they failed in their teaching as much as anything else.