I won’t lie, I feel like an outcast and I imagine majority of Lemmy are Millennials and Gen-X. The r/GenZ subreddit is mostly garbage but still want find an online community that is for Gen-Z by Gen-Z so I can use less of Reddit if possible. I know, I commited biggest sin on Lemmy for using Reddit.
I’m not sure if I would have the time and energy to make a community from scratch. Mainly just trying to sell the idea of Lemmy to people without sounding pretentious. Also, I did suggested Mastodon to my friends and was disinterested. Not going to lie, it did a hurt a bit as I do feel bit passionate about the Fediverse and I feel weird for being interested which most people in their 20s won’t care and using Instagram or TikTok instead.
For what it’s worth, there are a good number of younger users here but I don’t think people go around advertising it.
As for your question, you could try the more specific meme communities? For example
!bikinibottomtwitter@lemmy.world