is that because minimum UTXO size would determine the amount of verified identities possible?
100,000 sats = min UTXO
100,000,000 *21,000,000 / 100,000 =
100,000,000*210 =max 21 billion identities possible?
Discussion
The minimum uxto size doesen't need to be 100k, that can change depending on the value of sats. To create 10 billion uxtos (peak population), assuming 135 bytes per uxto, thats a max of about 10000 uxtos per block, it would take 19 years for each individual to have a uxto.
with what your suggesting, does the UTXO have to be dedicated for the Nostr identity or can it just be a stache of bitcoin that is used for other stuff?
and will the client be able to see the size of the UTXO, and allow users to see the size of the UTXO, or is all that cryptographically hidden somehow.
I imagine it could be any wallet address, not necessarily one dedicated to a single uxto. Theoretically it could also be a lightning channel if you can find a way to sign a message with the private key.
The red herring is that nostr will never need to scale to 100% of the population with this NIP. We can rely on the eventual growth of technology to solve the problem when it actually becomes one. Let's not optimize early fellow engineers.