I don't think this is a fair analogy. We're talking about ceasing to believe in red pandas without the universe helping; the 2+2=3 case had the evidence appearing all by itself.

I think I might be able to stop believing in red pandas in particular if I had to (5% chance?) but probably couldn't generalize it to most other species with which I have comparable familiarity. This is most likely because I have some experience with self-hacking. ("They're too cute to be real. That video looks kind of animatronic, doesn't it, the way they're gamboling around in the snow? I don't think I've ever seen one in real life. I bet some people who believe in jackalopes have just never been exposed to the possibility that there's no such thing. Man, everybody probably thinks it's just super cute that I believe in red pandas, now I'm embarrassed. Also, it just doesn't happen that a lot rides on me believing things unless those things are true. Somebody's going to an awful lot of effort to correct me about red pandas. Isn't that a dumb name? Wouldn't a real animal that's not even much like a panda be called something else?")