Fediverse

Looking back at my own life, I found the first few online communities I ever seriously joined (when I was a preteen, for context) through a web search, then discovered most others (recursively) from there, until I ended up (among other places) here on lemmy (which I can trace back to reddit, which I can trace back to a forum I started to pay attention to because of one of these original online communities preteen me found through a web search; not providing more info for privacy reasons). :P

So #1 and #3 are how it should work, IMHO, although #3 mostly for people who aren't yet engaging with anything at all, most things will be discovered through #1.

I think most people use the Internet not for posting anything (or at least not much) themselves, but for looking up things they want to know (through a web search). In the pre-smartphone era, web searches would often direct to specific websites which might have forums attached to them, that was how I first started to seriously engage in my first online community actually. This isn't the case much nowadays: many search results are either wikis (which are communities themselves, but don't really invite discussion that isn't about working on the wiki) or blogs/WordPress websites which may or may not have a comment section, but it's relatively rare for them to have forums or even to link to reddit/fediverse communities to discuss their subject matter.

So I think it would be desirable if we managed to change that last part: top search results for many terms on search engines should be, or link to, fediverse communities, which should make it clear that users are invited to join. That would help us get more users engaged with fediverse communities in the first place, they would naturally discover more communities once they're here.