- it allows specifying that http3 or http2 should be used. The former is especially important, since http requires using udp instead of tcp

- it can include certificate information used for ECH

- it can be used as an alias record at the apex of a zone. Which sort of solves the problem of not being able to have a CNAME on the apex... Once this is widely deployed.

Did you read Appendix C.1 of RFC 9460? It’s addressed in the very document. If implemented it can reduce time to first byte (it saves round trips to negotiate the next protocol) and it can be retrofitted to existing protocols like HTTP. If this is implemented by most browsers the SNI reverse proxy only has to handle remaining load.

Thank you for this. No, I did not, though now, I have. :)