A bit meta, but in parallel to migrating to Kbin, I also started playing with the news aggregator https://news.kiwistand.com/, which is a Hacker News clone for Web3.
As I understand it, a key difference from HN, though, is that Kiwi is an open protocol for submitting and upvoting links. It does not contain identity management features nor the ability to store comments and replies. All you can do, as a user, is connect your Ethereum address to post and upvote links. You also need one ERC-721 Kiwi NFT in your wallet to have the ability to post.
Clients are then free to build their own commenting system (similar to Kbin or Lemmy) on top of the Kiwi protocol. Those clients may store comments data on the blockchain (e.g., an L2) or on a traditional server instance (federated or otherwise), and they may use Web3 authentication, e.g. Metamask or SIWE.
I thought this community might be interested given the Web3 focus and the openness of the protocol. Read more at https://paragraph.xyz/@kanfa/what-is-kiwi (disclaimer: I have zero affiliation to this project).