In my experience, it is somewhat confusing for non-technically minded people to grasp the protocol side of things. I guess this aspect needs to be explained in a way that is easy to understand.
The way to sell the protocol to people would be to build some amazing apps on it, because I don't think the average person would care as much about the protocol itself, as long as they get the basics. Just like most people probably don't understand how the smtp protocol works, even through they use email every day.
"Your keys, your content - works with any platform running on nostr." sort of thing.
Agreed, and yes the existing apps could use a little more improvement first. Maybe Jack's right, search is what they're missing... We've already got some great starts just missing that.
I personally wouldn't even talk much about keys; I'd just show (in video form when possible) an automatic login using a wallet & LN-Auth. Everyone has a phone, this login UX is a great selling point.
I've been thinking about a script for such a video for a while now, mulling it over in my head. Waiting for search to be perfected could take another 5 years though; I need to draw a line in the sand and turn this into video before I get old and gray...