[aschmahmann]

The way IPNS uses the DHT faces some deep challenges if you really need the “latest” IPNS update (if you don’t there are various ways to make IPNS perform significantly better, see https://discuss.ipfs.io/t/ipns-resolution-takes-a-very-long-... for guidance).

There is also some work to make IPNS work over PubSub independently from the DHT. That work is being tracked at https://github.com/ipfs/go-ipfs/issues/6447, and should significantly improve IPNS performance as well as add in features like allowing users other than the author to keep IPNS records alive (so no 1 day expiration issues).

As for the decentralized nature of pubsub it is essentially an opt-in system. Random people on the network are not holding or forwarding your messages as they would in the DHT. However, anyone who has subscribed to a topic will propagate messages for you to other subscribers. This means subscribers do not need to directly contact the original IPNS record publisher to get a record, but instead can get it from anyone who has it and is advertising that they do so.