His meatspace introductions necessarily have an upper limit, but the Internet will instantly and concurrently bring down the law of large numbers upon him, where every whack job sharing every dumb FB post about how he's evil will have an opportunity to ruin his life, his and his employer's work, the patients that depend on them, and/or the lives of his cohabitants in all the same ways.

As someone who knows people who work in mental health I can assure you there are many security vectors available once someone's real identity hits the internet and social media. I'm talking about patients who are in hiding from pimps, abusive family or significant others.

It's no different than using HTTPS or CORS to mitigate security threats. You're essentially saying that since my acquaintances in mental health go to a therapy conference or a trivia night at the bar, that their personal lives should be exposed to the entire world in perpetuity. You're essentially saying that any SaaS should leave their ports open to the world for every scanner and scammer to exploit.