When I visit kbin.social, I see new posts regularly. On other servers posts stay on the frontpage for multiple days. This is also true if I switch their sorting to “hot”. So that is probably not the difference.
What is kbin.social doing differently?
That’s the magic of ActivityPub! It’s a federation standard that Fediverse services utilize to sync data. That’s why you can also view Mastodon posts on kbin (and elsewhere).
https://activitypub.rocks/