Today is my first day here and I've mostly just been wandering hobby/interest groups!
I think the biggest barrier for new users is that the whole system here is pretty complicated with the "decentralized"/"federated" model. I don't really understand what it means or how it works, and what the difference between the different servers are or what to join or even which app to use to access lemmy. There are a lot of options and complicated tech terms (like "fediverse") that you have to research just to even sign up. And I'm sure the fact that you have to write all of these long posts to explain it to people doesn't help. A platform like reddit (which I migrated from) is clean, easy to understand, and makes sense to the casual user.
As for the political stuff, I think people here should engage more with positive content. We should make the wholesome, fun stuff popular because it appeals to the mainstream. Post about the cool/funny/awesome/interesting stuff you encounter every day; talk about the arts, your hobbies, your funny life fuck ups, your pets, etc.! In my exploration today I noticed those kinds of communities barely get any interaction whereas the news/political ones are always active.