Then perhaps set them up with some of the WoT relays.
At this point the nostr experience is far from polished. You are not going to win someone over with the great user experience. You are going to win them over ideologically. If they don't get excited by what nostr represents then no amount of or lack of spam will make them "get it". And if they are not willing to push through some spam then they probably won't be willing to push through empty feeds, relays not connecting, notifications and replies not showing up, notes not being viewable and all of the other quirks that come with the nostr at this stage.