One of the most frustrating things is seeing someone's ENS and wanting to reach out to them but having no means of actually doing so.

Pasting the ENS into FC/Twitter/Telegram sometimes works but otherwise its just a dead end connection.

What's the latest on onchain messaging and how to "DM" someone to their wallet?

Onchain is the new online - FID 206 -  cooprecords.xyz

A few years back I would have said try Status.app but same problem as with others, the chance that they are signed up is nil. I would just send an 0 ETH transaction with the message in the calldata and some wallets may show the message, or they can check Etherscan.