As human beings, we are still animals. When it comes to dating, mating or finding our other half, we are also still dealing with natural selection. I think many try to disregard this natural process that plays out in the animal kingdom every single second of every single day, as antiquated and unfair to those that do not typically fall within the parameters that we as a society at large have decided, do exist when it comes to natural selection or attractiveness to a potential mate. These things are still in play, and they always will be because this process has ensured that generations and generations have survived as well as thrived thus far.
For example, if there is a short balding guy, he complains that women don't like him because he's short and bald and can't get a date, yet our society has decided that tall with more hair is generally more attractive than short and bald. If a woman knows a man will have trouble in life because of these qualities and it's been re-enforced through television, movies, parents, friends, social interaction, etc., she tends to select against those qualities in a man. The same goes the opposite way. If you are an obese female, society has generally decided that healthier or more fit females are considered more attractive and in this case, better for bearing children, and so men tend to select for that. Does it mean people ignore typical standards of attractiveness and go outside the norm? Of course it does, but not as much as they adhere to them.
This is natural selection. We as animals are selecting traits whether unconsciously or not, that may have bearing on our future children and their survival. Most of us won't be in the woods trying to fend off bears and building log cabins from scratch, but there is also social, emotional, and physical survival that occurs for us every single day and certain attributes can help those future children and even ourselves in a world that can be impossible, harsh, and cruel to them without them.
I ask then, how is it some fault of the members of our society for selecting these and other traits we deem, the cream of the crop? You see it all the time, these endless rants about how it's all the fault of women or it's all the fault of men for not liking a certain person because they are xyz. Natural selection has always been cruel and decisive. It's the father lion, killing his cub for fear of competition at it's worst, or rejection in human form at it's mildest. For an entire society to go against the natural order, would mean we'd be selecting for our own downfall or extinction. Natural selection favors the strong, the attractive, the healthy, those that are intelligent, and in our society, those that tend to be more wealthy or have earning potential. It is why the other half not naturally born with such gifts, works so incredibly hard to get any type of leg up they can whether it's make-up, lifting weights, plastic surgery, hair extensions, male enhancements, going to college, and on and on. It is also why those at the top also work hard to maintain their own status in society.
Rejection is a part of nature which has helped many a creature to survive and thrive through centuries including ourselves. To suddenly come to the conclusion that this century it is suddenly any more or less cruel than in the past, is ignoring a lot of what has gotten you here to this point in the first place. It will be for those that aren't the tops, to decide instead of complaining, to try to find their own way to get a leg up, that will in fact, get to go against the grain and push their DNA forward above those that sit back and accept essentially and passively, their own extinction by complaining about what they already know exists and doing nothing about it. You essentially have to do what everybody else is doing, and do what it takes to not be left behind.