E.g. If I were to share an image of a doggo on lemmy.world and then people from sh.itjust.works upvote it, will it count those upvotes? The answer to this one seems pretty easy to reason that it would be yes.
But what about if i’m on lemmy.world and am subscribed to !awesomecommunity@sh.itjustworks and I see it in my “subscribed” feed? Does this reflect total points across the lemmiverse or will this just show upvotes from lemmy.world?
I think an important take-away from this is that Lemmy pushes changes between instances, it does not synchronize. Instances get out of sync when changes get lost (as you describe) and I don’t think there is a mechanism for the destination to know it it out of sync with its peers.