Rudeness, obnoxiousness, kindness etc are such subjective terms. Some people consider anything but complete acceptance of their views and beliefs to be rude.
For example, my extended family is not only deeply religious, but also very conservative regarding what career I should have, what kind of girl I should marry and what kind of lifestyle I should have. When confronted with these ideas, I always reject them summarily. But according to my mother, doing so to their face is being rude and obnoxious.
My position is, as long as you are being honest, don't give a damn about being polite.
For example, my extended family is not only deeply religious, but also very conservative regarding what career I should have, what kind of girl I should marry and what kind of lifestyle I should have. When confronted with these ideas, I always reject them summarily. But according to my mother, doing so to their face is being rude and obnoxious.
My position is, as long as you are being honest, don't give a damn about being polite.