If I say I like cats, and you find an article saying someone else doesn’t like cats, that does not mean I’m mistaken on the fact that I like cats.
You seem to think they said that ‘everyone sees a difference’. They didn’t. They said ‘I see a difference’. They’re only ‘wrong’ about that if you think they’re lying to us about their own personal position.
They said they saw a difference.
They didn’t say other people didn’t see a difference.