great part of the privacy model is same for bitcoin addresses, not correlate npub to kyc identity, avoid reuse and separate identities. The other part is network-related, like use tor and, in future, we will see what would be the best way to send private messages.

Today dms are a mess, but for public notes if you use tor from a foss client like amethyst you dont give pretty any information to noone (except for what you decide to publicy share in notes)