As such, we respectfully ask writers to adhere to a few simple ground rules so that we do not expose public curators unnecessarily to content that may be inappropriate or offensive to them.

Nothing against "ground rules". Actually, it'd be best not to talk about rules all the times. Though I did recommend to the author that if he finds his story worthy of publishing it here (or elsewhere) he might just violate them and not ask for permission to violate them. There can be no "yes" answer to that. LOL

Since the theme was brought up - as it always is - I commented on it.

But the second part of your sentence I do object to. Would you yourself want a gate keeper for you having selected which story you might want to read and which you might find offending? Can you not decide that for yourself? Here are adults at work as curators, aren't they?

Now if I were a curator and I was assigned random submissions and one of them hurt my feelings, I would have several options: I ignore the story because I don't feel like engaging with the author. I ignore to curate all five stories and merely give feedback that I'm only curating four instead of the five, for example. What is the problem?
In the event that the author in question complains, I can simply tell them that they have not complied with the rulebook. Insofar as the author wants to initiate an interesting debate with me in terms of content, I can remain open to that or close myself off, from case to case. No one can be forced to do anything, either to read something or not to read something.

You didn't respond to my question about whether it's not more of a concern if no one really breaks the rules or makes submissions that partially or totally ignore the guidelines.

If you already call it "out of control" to debate or err or misunderstand, what is it you want? No debate? A flood of stories always adhering exactly to guidelines, with everyone just patting each other on the back and reassuring themselves how great they are? I'm being a little provocative on purpose.

Contact is always made at the border. These borders are not something that can be eradicated because they are indeed marked by cultural differences.
Anyway, I don't think the rules of Dreemport or even The Ink Well need defending. They are understandable. However, where someone does not follow etiquette, it can be interesting. There are great opportunities in conflict and in the realisation that not all problems can be solved because an attempt at a solution, for example, often exacerbates the problem.