Ok, so you get some critical amount of 'humans' to share "a" passport. Now you've built an expensive and high quality lead finder for scammers/spammers. You've increased the value floor for people submitting fake passports. Also, how are you paying for verification of the passports?, VC money to get from the loss phase to the making enough to support itself on ads? How are you dealing with government data requests, especially in the case where said data can be attributed to a real human?.
Maybe I'm wrong, but just a social network of 'real people' doesn't seem like enough in itself. What is going to bring people there with the restrictions and potential risks you're creating.
You could very well be right. I'm willing to give it a shot and see.
All I can say is that I personally see huge value in a social network for real people. Personally I am sick of arguing with what are likely legions of duplicate accounts/bots/russian trolls online. I want some reassurance that I'm not wasting my time and am actually reaching real humans in my interactions online.
Success to me is 1000 MAU. There are companies out there that do passport verification for a reasonable fee with a fair amount of free verifications to start with (which will handle 1000 MAU just fine). If the number of users wishing to take part is significantly higher then I will explore either ads or charging a small fee during registration.
I'm still very far from needing to cross that bridge though. Same for some of the other questions you've raised. I'd have to do a lot more research to come to a solid stance of what to do when government data requests come in. But I would guess that there isn't much choice but to abide by the request. If you want true anonymity from the government then this place will not be for you (but then I'd say not many social networks are for you in that case)