Politeness may be beneficial when navigating social systems, showing deference and respect, and reducing anxiety with decorum. Yet it is also a set of protocols. It mediates personal interactions until you can no longer be sure exactly who somebody is: politeness can be a mask, disguising the real you.
If you are seeking the authentic you, the unadulterated authenticity of the unique self, it would only be revealed when you are by yourself, without the distractions or pressures of others. Yet, who we really are might only come from the challenges of interacting with others, otherwise your conception of self is untested.