Trying to think of a way to use burner npubs for DMs. Seems like a good way to get rid of metadata leakage. But when you ask a relay for DMs for an npub, they can associate your IP with that npub and any others you ask for DMs for.
Discussion
When you start a new DM conversation, create a new account just for that person and send that new npub. They contact you with their new npub. And use VPNs, switching servers when switching accounts.
Yeah. VPNs and tor would do it. I'd like something built-in to a DM client. Tor could be but Tor sucks sometimes.