It's also unethical to make promises to users, like privacy for posts published to a semipublic social network, that software can't possibly keep. It's going to be interesting watching the norms of the fediverse collide with the expectations of ordinary software users. Mastodon and ActivityPub have a lot of promise as an alternative to centralized social networks, and there are good reasons to use them even if you do…
On the one hand it's bizarre from a technical standpoint to insist that Mastodon can't search or quote-post, when the software is federated and open source (so I can change my own instance to enable search and quote-posts), and when an API is available (so I can roll my own search index without even running my own instance). If you don't want your stuff archived and indexed by strangers you don't trust, then don't po…
Quote-post can be a problem because it encourages bad behavior among people who aren't actively malicious. If the most popular Fediverse software doesn't support it, there won't be a widespread quote-poste -> pile-on phenomenon even if a few servers support it without getting widely blocked.
Search becomes a problem when a group of bad actors use it to harass and dox people. It doesn't require widespread adoption, just a small number of bad actors with access to an index. From what I've read about previous organized far-right harassment campaigns, I find it likely that bad actors are already indexing Fediverse posts, but not publicly talking about it. Excluding search features from the most popular software will not help with this. Blocking servers that admit they're indexing posts for search will not help with this.