I find it much harder to explain Steem than Bitcoin. Bitcoin is easy. I usually start by asking if they understand how BitTorrent works - then explain that instead of everyone sharing whatever file they want, we all share the same file, which verifies its accuracy. Steem is tough because eventually they want to know where the money comes from, which means you have to explain PoW and PoS algorithms. Proof of Stake is something I find very difficult to explain without making it sound illegitimate. "Oh, they give you more money for holding money in your account and not spending it." I say, and they reply: "So it's a pump-and-dump scheme that only the founders can profit from?"
Such is the life of a crypto enthusiast.