When I want to pull someone in, I'll mention that I saw some meme / post / video or whatever on lemmy, and then tell them about the post. You're leading with the value of the content, and if the person you want to join also enjoys that content, they might ask what lemmy is. This is your invitation to pull them in.
This. Marketing 101. Tease with content, not with technology.
This. Marketing 101. Tease with content, not with technology.