Yes, but having it be disjointed from the protocol adds friction. You can't just browse the files using native tools and gateways. I think it would be great to be built-in.

In fact I would argue that all data should be encrypted. But by default it could be encrypted with its own hash or similar so that it can still be deduplicated but has strong protection from people who don't already know the content (or hash) and can be pinned on untrusted nodes. This would resemble the Google Docs "public link" sharing. The only downside would be slight CPU overhead and longer keys.

You can do that and also require auth to retrieve the cipher text blocks: https://peergos.org/posts/bats