I'm not saying your work is a wasted effort, bcs right at the beginning of the paragraph that you're citing, I say 'naturally through friends' - that's exactly the best way to onboard someone and pass some trust you have to them. 

I watched your video, looks great and I fully support your effort. 

All I'm saying is that if someone has NO friends on nostr and joins nostr then they're indistinguishable from a bot. In fact, on Nostr they're much more likely to be a bot bcs it's an open network. And if they have to prove they're worthy of trust/attention by organic interaction then it will be hard bcs bots will be much more productive and persistent in attempts to gain trust by liking/commenting etc. For such people with no friends, doing PoW or paying fees seem like the only options to outpace bots.