A PDF with my comments marked up inline can be found at
https://1drv.ms/b/s!Aqj-Bj9PNivcn_tvdayAlL9xJZJgKQ?e=K42XOF

Overall the document is well written, and easy to follow.
That said, I have several specific suggestions:

Section 2.1.2 (MLD): The registry itself is labeled as policy “IETF Review” but the words “IETF Review” per se never appear in RFC 4443.  I’d recommend explicitly saying IETF Review here.

Section 2.2 (Resv Bit): This column heading is confusing. In RFC 9279, the “Resv” field is only 3 bits wide, whereas in RFC 3810 and 3376 it is 4 bits wide.  And in both 3810bis and 3376bis it is called “Flags”, never “Resv”.  I'd recommend "Flags Bit" for consistency with 3810bis and 3376bis.

Section 2.2 (values in the Resv Bit column): These values may be hard to understand. I’d recommend explicitly saying this is the value of the column header in the packet format diagrams in 3810bis section 5.1 and R376bis section 4.1.

Section 2.3 (values in the Flags Bit column): Likewise I would add a sentence explaining the bit number corresponds to the column label in the packet format tables in 3810bis section 5.2 and 3376bis section 4.2.

Section 4 (Contributors): currently says "RFC 3228 ... forms a portion of the content contained herein".  I recommend changing "forms" to "provided".

Section 5 (Acknowledgements): This is an empty section.  Remove it or fill it in.

Section 6.2 (Informative References): I think 3376bis and 3810bis are both used normatively, not informatively.