I’ve had a small breakthrough here in a way that helps people understand, especially if they are Reddit users.

Have them pull up r/all, and just scroll a few posts and tell them to imagine that every subreddit is interestingasfuck@reddit.com, pics@reddit.com, gaming@reddit.com, etc

Then explain that Lemmy works the same way, except the content doesn’t all come from one website. It’s part of a network of sites that have agreed to an open protocol so everybody can share information freely.

You can explain the pros and cons if they’re still listening lol. But this seems easier for people to conceptualize, for whatever reason.