People shouldn’t have suggested you Beehaw.

Nowadays, I just say

Lemm.ee is a Reddit alternative. There are apps you can use from https://www.lemmyapps.com/, just remember that your “instance” is lemm.ee. It works similar to Reddit".

That’s it. No federation explanation, no Fediverse jargon. Keep it simple. Also, see my other comment below about an active community of non tech users