That's like asking a rape victim to show her bruises publicly or you won't believe it. Pics or it didn't happen applies to lots of stuff but when there are a lot of people with pretty good reputations making the exact same claims then you might want to give them the benefit of the doubt.
Facebook is not above making mistakes and the number of people right here that make these claims is too large to simply be ignored or waved away. Clearly something has changed for some people, now the question is how many people are affected and what can be done about it.