I’m wondering if this is some sort of Google Console bug since comments in comments are optional. Here’s the schema: Comment - Schema.org Type.
The schema validator from schema.org is also indicating that our structure is good – 0 warnings and errors: Schema Markup Validator
However Google’s Rich Results is showing a glaring “
Missing field “comment” (optional)”: https://search.google.com/test/rich-results/result?id=mZ6z7ZtXJe0XE-YYnmY96Q
I considered commentCount=0, but I hesitate to modify this when I don’t think this should be the fix. Sorry for the laser mention @rrlevering, do you have any input why optional comments in comments are now showing these warnings as seen in OP?