Governments and some massive corps can intercept IP and make their server be the real one. Worse, for you it will still look like your server is replying. You wouldnt even notice they switched your server. This is especially true for nostr relays. They can just put up their own relay MITM and start tracking everyone that connects to them.  

 👀  

 You could still use npub to handshake and upgrade to TLS without replacing IP with exotic new technology.