“You are demonstrating that you do not trust the relationship enough”

This is entirely rational when a relationship is not strong, and a misstep could cause it to sour in a way not easily remedied. If I have to work with you, and can’t fire you, then I don’t want to foul the nest.

As my coworkers get to know me, they will drop the unnecessary politeness automatically, according to Zipf’s law. They will find I react well to straightforward communication once we have established trust.