That's pretty much par for the public dynamic of this community. And, as noted above, such a policy doesn't need the community at-large's approval: it's a document that constrains those that wrote it.
If that is the case then it is of no real use as only a handful of people wrote it. Otherwise could you explain what you mean?
The core committee can, if they so choose, e.g., remove someones login from postgresql.org, period. They don't *need* a published code of conduct to take action in situations they deem to violate whatever code the members collectively hold to. But making it public and publishing a corresponding dispute resolution process brings a level of openness and formality to the process that benefits the community as a whole. While input from those the Core Team serves is valuable at the end of the day they are a benign dictatorial committee when it comes to official PGDG policy and actions and this document is their group think made manifest for others to learn about and provide feedback as to how they would wish for the Core Team to behave.
And, since the Core Team is delegating the role of community policing to others, a document detailing that is needed for those other's benefit if nothing else.