Correlation does not imply causation, it's quite possibly a coincidence. We've had more diaries this year from Dr. Paley and Dr. Rozbruch too, is there a conspiracy theory for them as well? The simpler explanation could be that it's confirmation bias, since many disagree with Dr. Mahboubian's marketing strategy. Perhaps the truth is that more people have found this forum and that the economy has recovered enough for them to choose American doctors.
As for proof, every photo uploaded is an increased chance of getting doxxed, so I don't blame those who prefer to not share a thing. I mean, do you want to end up on Encyclopedia Dramatica like Apo?
They probably won't put in the effort to go that far, but you'd be surprised at how crazy some people are on the internet, including forums like this one. They'll reverse image search, compare writings, match up unique identifiers, find social accounts, etc. Not very hard to do when some overshare by posting photos without careful review, phone numbers, or reuse usernames on old forums.
This is why I suggested in the past that perhaps patients could bolster their credibility through
a verification process with the mods. No need to show a ton of images or details publicly; they've been vetted and that's enough.