Huh. I guess I am naive in my optimism about the human race. I'll be the first to admit that we have a lot of nasty awful dysfunctions, but I'd also point out that humanity isn't static. We do change over time. Yes, sometimes the changes are for the worse. But overall, the balance of all the changes weighs on the side of the good, as long as one backs up far enough to view enough of the timeline.
It wasn't that long ago that two men holding hands and kissing in public would have been met with as much widespread horror as a man undressing in public. In fact, a lot of people are still really uncomfortable with homosexuality, to put it mildly. We are still on that journey, the journey toward accepting diversity in sexual orientation. We are also on a journey toward accepting clothing-optional scenarios, but we haven't progressed nearly as far in that journey.
It's too bad that lots of people dress and groom in a certain way because they were pushed into the mindset when they were kids, or because they're desperate to fit in, or both. But people still have to make their own decisions about their own bodies. They can't always blame their parents or existing peer pressure. Polyamory wouldn't exist today if there weren't people who were willing to "resist the system."
I don't think of it as a "hatred thing." It's more of a "fear thing." What will happen to me if I don't conform? What if people stop loving me? What if they fire me, take my kids, throw me in jail? These are the kinds of things that convince people to act conservatively, even if somewhere in their hearts they'd like to throw off the shackles and be free.
Yes, we are taught to hate ourselves. What usually results, however, is that we learn to fear ourselves. The Catholic Church did a good job (over the centuries) of spreading sexual and bodily shame across the West. But hate is usually too strong of a word for that. It's more common for people to hate each other than it is for them to hate themselves, though some people certainly do learn self-despite and the lesson sticks.
Let us not add to the problem by forcing (even just in our fantasies) other people to throw off their chains. Let us set the example of live-and-let-live by letting other people choose if, when, and how they'll throw off their chains. And maybe they'll still dress and groom conservatively, but maybe they'll innovate their lives in some other less-obvious way. That's still progress.
And also, just as not all monogamy is caused by conditioning (even if most of it is), not all conservative appearance is caused by conditioning (even if most of it is). Again, it's all about diversity. Let's not try to get all people to change from one look to another, let's just be encouraging and accepting toward all people for however they do look (even if they're doing it for the wrong reasons). People are smart enough to learn how to accept themselves given time and generations.
I actually don't believe that the natural state of humans is nakedness and a full mane of hair. Our brains are too darn big and busy to go that way all across the board. Instead, I believe that the natural state of humans is a wide range (a range that certainly includes nakedness and a full mane of hair) of self-expression. As long as we get over the conditioning part of it, let's not fret over the "many strange ways" people choose to present themselves to the world.
I don't think we're a very advanced species. Someday, people will look back on how we lived today and (rightly) think we're quite primitive. Just because a skyscraper is more sophisticated than a chipped spearhead, doesn't mean that the builders deserve to be called advanced. I think it would be quite impossible for you or I to imagine what life will be like a thousand (much less a million) years from now. But I do have faith that it'll be a hell of a lot better than it is today.
"The decent moderation of today will be the least human of things tomorrow. At the time of the Spanish Inquisition, the opinion of good sense and of the good medium was certainly that people ought not to burn too large a number of heretics; extreme and unreasonable opinion obviously demanded that they burn none at all."
-- Maurice Maeterlinck