For example: I don’t believe in the axiom of choice nor in the continuum hypothesis.
Not stuff like “math is useless” or “people hate math because it’s not well taught”, those are opinions about math.
I’ll start: exponentiation should be left-associative, which means a^b should mean b×b×…×b } a times.
“Terryology may have some merits and deserves consideration.”
I don’t hold this opinion, but I can guarantee you it’s unpopular.