It might be easier to discuss this if you cite some excerpts of posts so they can be discussed for all to see.
Nevertheless, as someone who declined some of those flags I can give you an answer without going into post specifics that might be helpful.
I think the main reason for these flags getting declined stems from different interpretations of the code of conduct. In your meta question, you write:
I think it's transparently obvious that this sort of conduct is rude. It tends to marginalize people with differing beliefs, by making them feel that their views are not respected, or even that they're getting propagandized against. In Code of Conduct terms, I consider that such content meets the standard of "...unkind, cruel, or mocking comments that provoke or insult another person", and/or "the poor treatment, expressed irrational suspicion... and/or intolerance of another... group of people due to [their political affiliation]".
The code of conduct portion you're referencing is the one on Bigotry and Discrimination which reads:
Bigotry & Discrimination – the poor treatment, expressed irrational suspicion, hatred, targeting, and/or intolerance of another person or group of people due to their ethnicity, age, sexual orientation, gender identity and expression, disability, or held religious beliefs.
The code of conduct mentions a number of protected categories but it does not mention political affiliation or political ideology. I think that's because we want to allow criticism of political ideas as long as the post is useful to the site (questions that aren't otherwise off-topic and answers that actually answer the question) and it doesn't violate the code of conduct (again, in my reading political beliefs are not a protected category).
I'd further note that there's another code of conduct page on political speech which reads:
Harmful political content policy
The spirit of this policy is to create and maintain rules and guidelines that allow users to share knowledge and discuss challenging topics safely and peacefully while still allowing a decent level of scrutiny to governments.
We do not allow advocating for violence or encouraging harm to others. We do not allow discriminatory content towards a person’s actual or perceived ethnicity, age, sexual orientation, gender identity and expression, and/or disabilities. We also do not allow content that supports, celebrates, or furthers the cause of extremist organizations as per our Abusive Behavior policy.
While on our sites users are expected to be factual, respectful, and objective while participating in main Q&A, user profiles and chat rooms allow for more subtle and nuanced conversations where pointed or harsh criticism of political figures, their policies, and governments (including satirical statements) can be allowed as long as they do not otherwise violate the Code of Conduct and do not contain insulting language directed at individuals.
Additionally, we will not allow political misinformation or widely disproven allegations against a political figure not supported by reasonable evidence to be promoted on the platform. Read more in our Misleading information policy.
In that spirit, it's of course best if posts are written in a neutral tone, critical arguments are written in a constructive way, etc.
To get back to the issue of declined Rude/Abusive post flags, there's only a few things we can do as moderators:
Mark it as a helpful flag but not take any action. Unnecessary flagging is not really a behavior we want to encourage. A flag that sees no action just takes up our time reviewing the post. If no action is necessary then we'd rather it didn't get flagged.
Decline that flag and take no further action. This is the default option (at least for me) when a flag doesn't warrant moderator action. It's my view that that's what happened with the declined flags.
Delete the post. If the answer is clearly a code of conduct violation and it is not easily salvageable through editing. I don't think post deletion was warranted in the cases of the flags I declined.
Edit the post. If a code of conduct violation is present in some portion(s) of the answer which can be easily removed so that the rest of the post is worth keeping then this is an option for us as well. I don't think that applied to the posts you flagged because those posts criticized some political beliefs which I've argued is within the bounds of what the code of conduct allows.
Finally, there's some other things you can do. All of the above is just talk about the code of conduct and using RA flags, but it's of course no endorsement of what was actually written in those posts you flagged. If the posts are flawed content-wise then options to tackle that are:
- Leaving a comment pointing out a clear flaw or asking the poster to reference a dubious claim. In your post you mention the use of false experts, that's something you could call out in a comment.