That simply isn't true. I'm a nobody and plenty of folk have found me from seemingly inane posts. People have found me out of the blue, from across the Fediverse, and I have no idea why; all I do know is we now chat frequently and without either of us even looking for one another. What's impossible is to discover how to use a platform without reading the documentation, and assuming that algorithms will just do the work for us.
If you use a popular instances your account will show up in searches, likes and other things.
But when using an independent server, one would need to type your full username, and then try and see if such an account exists.
if you only type the display name, or username without the server address, nothing will show up.
Which is fine for chat apps like Matrix or E-Mail, but not for platforms where discoverability is important.
You know what else helps a lot? Getting in quality conversations with others, having something relevant to share with others, etc. IOW, by being social.
At this point, it seems like a feature that the system does not make it easy to be discovered.
