For those who are new here. 

Nostr is a decentralized technology that enables secure and private communication without relying on central servers. Its numerous possibilities include social networks, messaging systems, and content publishing, with a focus on privacy and resistance to censorship.
 https://image.nostr.build/6f9d645ce5713c70efb796920a7282615e039a280b3315b0df44cd20245d39e7.jpg 

 Yet you can see everyone someone is messaging  

 You are correct