Dear all,
I am an assigned INT directorate reviewer for draft-ietf-dnsop-rfc8109bis. These comments were written primarily for the benefit of the Internet Area Directors. Document editors and shepherd(s) should treat these comments just like they would treat comments from any other IETF contributors and resolve them along with any other Last Call comments that have been received. For more details on the INT Directorate, see https://datatracker.ietf.org/group/intdir/about/

Though not being a DNS expert I think that the document is very useful, well written, and complete for the time being to help improve security and reliability of DNS practice. I have only few very minor suggestions for IMO improved readability:

P.1:
current NS Resource Record Set => current Name Server (NS) Resource Record Set

P.3:
for the IN class. => for the Internet class (IN class). /perhaps add ref. (e.g. to RFC 1034)

P.4:
Therefore, it is important that resolvers be able to => Therefore, it is important that resolvers are able to

P.8:
and it gets a query => and it receives a query 

Thanks and best regards
Dirk