Internet discussion boards serve two purposes. The first is information exchange, the second is entertainment. I think a certain amount of levity advances the second.
A secondary goal of that post was to contribute to a culture where it is understood to be OK to not know everything, rather than making statements that aren't grounded in personal understanding for the sake of trying to create the impression that a poster is in the know. Yes, I really do think about things like that. I suspect that many people respond to topics with opinions based on things they see in charts or other posts. That muddies the water with regard to information exchange. For example, the subject of ZT Elmax obviously leads to people who never used it posting about ZT's poor treatment of the steel.
Tl;dr: it's rarely a bad thing to make people smile, and "I don't know" is a better contribution than regurgitating info of questionable origin.