Inter-Planetary Name System (IPNS) is a system for creating and updating mutable links to IPFS content. Since objects in IPFS are content-addressed, their address changes every time their content does. That’s useful for a variety of things, but it makes it hard to get the latest version of something.
IPNS is not human readable. And the names are not assets on a blockchain. A .crypto domain is an Ethereum asset that relies on the security of the Ethereum blockchain. You sign a message with your private key and associate your IPFS hash with your .crypto domain.