Well, I hate to break it to you, but when your opinion is outright ignorant, I don’t think it reasonable to call it unpopular. It’s just wrong. That’s not even word play, it’s just the condition of subjects where there is adequate evidence to work with.
I suppose you could just call it an empty opinion, if you were wanting a less accurate way of looking at it.
But the truth is that willful ignorance isn’t an opinion, it’s just stubbornness and stupidity rolled into one.