Maybe, but I think there are social contracts that you are overlooking. If I write a rule, and then I violate a rule (or refuse to censure someone for violating a rule) then I can be rightly accused of hypocrisy.

People believe themselves to be within a certain margin of "good people", and having incontrovertible proof of being "The Biggest Hypocrite" makes them uncomfortable.

There are of course those who don't feel that discomfort; there are even those that commit victim-filled crimes without remorse. Often, there are external forces we can lean on to bring those people into line or out of society - and agreed, in the case of Open Source Software communities, those external forces don't always exist or are not reliable for regulating something as insignificant as moderation policies on a mailing list.

There are also those that would leverage that discomfort for their own immoral benefit, and bad rules are equally good enablers of that kind of person.

But I don't think it's fair to say that the quality of rules is meaningless - if there is any level of accountability in the sub-community of moderators (or in the community as a whole), good fair and enforceable rules have power.