My detailed comments and in-line text suggestions can be found in the PDF file at https://www.microsoft.com/en-us/research/uploads/prod/2022/01/draft-ietf-opsawg-mud-iot-dns-considerations-02-DThalerReview.pdf

Some high level comments:
* While I think the document is on the right track and I agree it is good to do this document, a number of the statements in the document are ones I disagree with as phrased.  My belief is that the wording can be corrected and in many instances I have proposed such changes in my reviewed copy.
* Some of the recommendations in the document are not sufficiently justified at present.   They may still be the right recommendations, but it means that more work is needed in the document to provide sufficient justification.  In my detailed review I have called out a couple of counter examples which the document should either address, or change the recommendations to accommodate, whatever the WG can get consensus on.
* A number of parts of the document still contain "todos" (some marked with "XXX", some not), so will need another IoT-Directorate anyway once it's complete.
* The document needed an editorial English pass, which I have done and provided a bunch of simple editorial suggestions in changed tracked text.
* There are several undefined terms in the document.  To broaden readability since we want this to apply to IoT manufacturers with a wide variety of backgrounds, technical expertise, and level of familiarity with the English language, definitions or at least citations should be provided for such terms unless they are removed.  I have called these out in the doc as well ("S3 bucket", "QuadX", "forced circuit proxy", etc.)