Remember to distinguish between teacher and school teacher.
Without teachers civilization could not survive. Perhaps neither could the species.
But under kleptocracy, teachers get hemlock poured into their ear, get crucified ... These days, crucifixion no longer being popular among kleptocracies, teachers get the rug pulled out from under them in a variety of ways: they don't get published, they get side-railed.
Perhaps worst, they get replaced by school teachers.
School teachers get mass produced by the state. They're so ignorant they don't even realize that they're not teachers; they're robots for the school board: and the school board is never made up of scientists, philosophers, scholars ... truth tellers. It's made up of politicians and political appointees: they'll say that the earth is flat: until told to say something else.