It's a dialogue; whining/dialogue, tomato/tomatoe? The last thing one should do with a dialogue is stifle it and the purpose of dialogue itself is to promote reconciliation and therefore the attitudes and arguments of individuals will change. If the dialogue is removed there is a good chance that either party will simply refuse to re-enter any sort of dialogue in the future because they will view their viewpoint as fixed and the dialogue itself as a broken system not to be encouraged.
I'm incapable of mediation, but I think every opinion is an important part of representing what did happen, what should have happened and how to fix it.
Addendum: I'm also not in the business of telling other people what they should or should not be serious about because of my selective definition or by even informing them what I think they should or should not be serious about. It's a serious flaw in perspective to assume that others holds the same axioms as the self and people make their home and set their boundaries based upon themselves and their own comfort levels, not upon the demands of others.
I won't raise that concept again, because to put it quite simply; it is damaging in itself to present that viewpoint because it closes itself out by being stated.