In more condensed language, with a different spin, I think what people are worried about is "If I append this group to my identity, will it cause people to dismiss my thoughts and arguments?"

If you tell most people you're christian, it doesn't cause them to tune you out immediately (except in certain subcultures) because christianity is an accepted influence on our culture. If you tell them you're anticipating the singularity...well, all bets are off.

So I suspect most aren't fearing being wrong, they're fearing no longer being credible to the people they normally interact with.