I only know that one time an obscure thing I was talking about here on kbin.social, perhaps as a response to a post on some Lemmy or another, ended up being indexed incredibly quickly by Google regardless of however things are structured in URLs.
This became apparent when I tried to do further research on the topic and I found myself staring at my own comment as federated on yet another Lemmy.
As long as search engines remain as on the ball as whatever happened there, we might actually end up with a repository anyway.