That's an interesting discussion. But I think it all diverges when you put "anonymity" as a pre-requisite. Maybe not every person would want that. Have you thought about it?
Or maybe there will be new mechanisms for protecting identity while still maintaining anonymity. At the end of the day, you need to know if at the other end of a transaction is a bot, or a real person, wouldn't you? So identity would be needed and identity shouldn't necessarily impact privacy.
It does seem to be a tough balance. How do you verify security without verify the human aspect of the transaction?