That was neither opinion nor fact. -- it was a lie! I just couldn't resist! 
Thomas, some folks a rude, some folks simply don't communicate well, and others are indifferent. Me, I'm old school, and like you, I prefer good manners. I also understand and accept that communication and language evolve. IMHO, evolution from "in my (humble) opinion" to "IM(H)O" is far enough, and I prefer some sign attempt at politeness, particularly when, as Art so aptly wrote, nuance is unavailable in large part.
Best,
Jed