Is it possible and does it make sense?
You can browse some cool P2P-websites (work without any servers) inside the network through this gateway.
Or you can browse them without any gateways if install Zeronet binaries: Zeronet.io
Is it possible to make some Ethereum smart contract be the owner of a site like ZeroID?
Well yes. They aren't like zeronet they revolve around a different architecture. But p2p websites is generally the vision of web3 and what ethereum runs on. Essentially the blockchain is your database and your server and since it is run in a decentralised fashion, then yes, a p2p website it very much is. However ownership is hard to define. Its very difficult to "own" a site without some very careful programming on your smart contract aspects.
