Microcosm Feature Suggestions

2) The notion that a private message is private is a fallacy today, but with increased transparency about when your messages are forwarded and shared fewer people will do so and they will be more private.
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So where's the concern?

Logically that makes perfect sense. In practice I think people are too accustomed to the idea of 1-to-1 conversations, even it's an illusion. Are you confident you can persuade all users to understand this?