It is basically email on steroids.

You write an email (note/message) but instead of sending it to one server, you can send it to multiple servers of your choice. Each message is digitally signed with your keys and a time stamp, so you can verify that the identity is truly yours no matter where the message came from.

In my opinion is the most innovative way of communicating that I've seen in the last 20 years. There is no concept of server nor permanent location.

A relay can refuse to receive your messages, but they can't block your account because you can always write new notes, sign them and send to wherever people want to read your texts.

Imagine the case with Trump when he got blocked from Twitter. With a click of a button they have deplatformed him, with NOSTR he would have just continued writing and people would simply tune to another relay to keep reading his texts.

On top of that are other good developments. For example, file sharing also became decentralized. So files, images and other media can be sent to the relays and you mention them from the notes based on the file hash which is good save content when someone else hosting your texts and media decides to stop hosting.

Nice way of phrasing it :-)