There is a large difference between constructive criticism and blatant attacks, especially in that the former will generally be accepted and the latter will generally get you in trouble with the moderators. So yes, these forums are in part a way for us to give feedback to SE. Just because there are rules against outright slander does not mean that they don't want to hear our criticisms. All they are saying is that it needs to be done with a degree of civility. If you complain for complaining's sake and do it in a crass way it's unreasonable to expect a favorable response.

