Actually, if anything a student who disagrees with me is more likely to get a high mark - because he shows he must be thinking for himself.
Parroting back my own ideas will not get you good marks in my class. It’s not that agreeing with me is bad, it’s that you need to make it clear why you agree with me, not just that you do. If you’re just trying to suck up to me, it won’t work out for you.
And it’s not about ‘expressing (your) views instead of teaching are being coercive.’ It’s about not concealing your views while you are teaching.
My country’s current opposition leader was a student at my school. Our current Prime Minister was a student at our brother school in Sydney - quite literally the opposite sides of Australia’s political spectrum. (Note, both of these were students at the schools well before my time as a teacher). So I’m also not necessarily teaching the ‘average’ students. My school produces its fair share of my country’s leaders. And part of the reason we succeed in that is because of how we teach and how we are allowed to teach.
Well, in an elite school for future leaders, I’d say the rules should be different. My concern is for the regular schools that teach the average students who just want to muddle through and get a job doing something they don’t find repulsive. For them, I’d prefer that boundaries be set, and the easiest way to do that is permit any sort of dialogue anyone wants in the hallway, but not as part of a class.