I know most people are just expressing their own position. Most of my objections have been to this specific sentence.
The bottom line is as much as some guys hate to admit this, there is really no such thing as "just friends" between males and females of ripe mating age. (say, 18 to around 45 years old or so).
It just speaks as an absolute that, if anyone disagrees, they're lying to themselves. It's just not the case. It may very well be the case for many, if not most, men, but to present it as an absolute it just not true.
It's not even the case for most men. If most women for you fall into two categories a) not for (lol) boinking for a really good reason, so I won't be thinking about that b) possibly for boinking, so even if it shakes out differently and we become friends, she's still subconsciously in that category - that means you don't see women as people in a way that you do men, and not all men share your opinion. There's very, very, very few straight women who think about men in this way, so it's not a feature/problem of sexual attraction to the opposite sex, it's about how some men see women as some sort of a collective pool of sexual resource to tap into in life, and not like a population of people who are just like you.
That doesn't mean it will manifest in real life, you could learn how to behave like 18th century nobility around women even as a young horny guy and none would be the wiser and these would just be your private thoughts. But it is kind of a personality flaw. It also contributes to this awkward area in relationships where guys have to tiptoe around having female friends, because if you have one boyfriend who admits he'd never have a platonic relationship with a woman if it wasn't for objective circumstances, you'll want to put an unnecessary and unfair leash on your next boyfriend, just in case.
That's only American Men though. There are vast cultures that view women differently. One mindset/perspective does not equal how all Men and Women throughout the world think.
You know how my people treated women, we treated them with respect, and held them highly. Women are the basis for our social structure, and is how we view the world. We don't view it in the Father/Male sense, we view it through the Mother/Female sense. The women decided which man to be with, Men had to do things in order for them to marry them, they build them a house, and that house is the womens womb and home, her responsibility is to take care of that home, as it houses her and her children. The house is not the mans, the only thing that a man takes care of in this sort of responsibility is the fields where he plants his seed in the womb of Mother Earth with his planting stick.
Due to this, women also viewed themselves with respect, and understood their roles and responsibilities in our societies. We are clan based, and our lineage traces back from our grandmothers. In order to save a clan, one has to strive to have a female, and we know what that means. Her responsibility in this case for the clan is to reproduce until she has that daughter.
Cultural roles, and responsibilities play into account on how Men treat Women, and how women also treat themselves.
American Men and Women roles and responsibilities, what are they?
Also, Sex is a natural process that everything does to reproduce and multiply. Some are asexual and can reproduce by splicing itself and creating basically a clone of itself.
Humans themselves are the ones that give this natural process meaning. Animals have that instinct to reproduce and will search out for that, and also each species has their own way of mating and flirting.