The problem is a little unique here, though, don't you think? Most of the time such things are said about TF2 players in jest (if not with a little truth), we all know we should take feedback with a pinch of salt and as individual authors we can choose to ignore the less relavent comments and dilute them in a pool of other experiences to get a better understanding of the reality of the situation. "Players are dumb" Is merely an equivalent way of saying "sure, you got mugged just then, but at least you have your life"; to look at the bigger picture and don't feel so bad about it.
The "disdain" comes down to the fact that these ratings will be considered in the final calculation on equal terms with ratings by "people with appropriate filtering", ratings that include revenge votes from butt hurt players with biased opinions made from insufficient data.
A player should realise that when their team lacks a medic on offence that they will not fair well against defenders who do. That their loss is as likely to be from their team make up and/or skill as much as it is the environment design. But players, or people in general, don't like admitting fault on their part because it is humiliating. Rather, they retaliate in anger by blaming the author and the layout design for mistakes by other players/themselves. I'm not sure where fine tuning of win rates really resolves this situation. Especially when the notion itself is odd considering these projects were all made within a time limit; fine tuning doesn't really come into it.
*A vote should not be cast off a single isolated experience.
*When evidence to the contrary of your understanding is presented you should not be stubborn about your initial experience and accept that this is not a valid fault int he grand scheme of gameplay.
*When your team is steam rolled you should ask yourself whether it was your teams class make up, skill or experience on the map first: Some players will have more knowledge than you to exploit and that is not the maps fualt.