The version code hasn't even hit 0.2 yet. Lemmy was founded by people who got banned from Reddit for being too toxic & extremist leftists, so went off to make their own replacement. They do what they like, and bc Rust is a difficult language to work with, not that many are willing to help.
Then after Huffman's debacle, we started to see Kbin, Mbin, Piefed, Sublinks, and perhaps more - but none even as advanced as Lemmy yet.
But more to the point, that's just the nature of an open network. Wouldn't Wikipedia suffer from the same issues? Though less of an issue than a social media framework I would wager.
The developers of Lemmy do not seem interested in anything less than banning people instance-wide, even from communities that they have never posted in before, so ironically shadowbanning is too subtle for them.
But I thought the only way someone could be shadowbanned now is at the individual user level? It would be nice to increase transparency even further - e.g. a message pops up if you try to reply to someone saying like "this user has blocked you" (possibly everyone from that instance) so that people do not waste time trying to get a message across that the recipient will never read.