yeah, of course it boils down to trust and "loyalty" of receivers not leaking

having public key of users you can do symmetric encryption of content and distribution of only such key for each viewer (be it pgp style or whatsapp groups or any other way to achieve "group encryption")

would be a way to take heat off relays (they cannot censor / cannot see content) and also basically have an hidden profile (only metadata leaked as in time/size/amount of recipients) accessible for example only to subscribers. 

or for example send them the symmetric key when a certain amount of sats thru zaps is sent... sort of like medium style "articles" with "pay per view" on each post, some posts or how you desire