I understand what you said about community rules. But the funny thing about the Fediverse and how people receive their posts is that it's not uniform. I'm in kbin on a phone and I don't see who is posting from what instance unless I click further. Same for the community or magazine someone is posting in - I can see that on my feed but once I click on a post I cannot see it. I've joined many communities and magazines and they are only identified by the topic name in my feed, not the instance. I cannot see any community or magazine rules from my feed or inside the posts.
Just saying that easily identifying a group's rules is more of a challenge in the Fediverse (this is not an argument to ignore rules).