I looked at your public profile 6th Dan Judo /7th Dan Aikido .You set about a Nidan , showing him the error of his ways.I would have thought that you being graded in the above disciplines, drubbing a nidan would have been easy peasy.In Glasgow where I was born and bred you would have be known as a Liberty Taker.Joe.
It *is* a martial art, someone at nidan level *should* be able to take decent ukemi, and it was a class setting. I don't see what's so terrible about providing a physical demonstration of one's skills when one is requested. Maybe if more people were able/willing to respond in that way we'd hear less BS about how "aikido doesn't work."
I'd be more interested in hearing the person's teacher explain how someone with such a complete lack of manners or humility managed to get promoted to nidan.