Sex relies on many superficial considerations, like focusing on the few and tenuous attractions that usually require a lot of concentration to maintain and to blot out aversions/ignoring the many disgusting features of the body. The basic act is mechanical and uninteresting. The verbal and mental work involved in courtship between minds (the concentration involved in maintaining mental sexual attraction and avoiding aversion) is enormous, and without mental attraction, there isn’t much physical attraction either. And the amount of pleasure it produces, while it can be intense, is short-lived compared to the hours of work involved. I am not talking about love, but sexual love and infatuation are not the same, take more to maintain, and are much less rewarding than real compassion and kindness.
The fact that the entire world can be described in terms of sex is not profound. Any pair of opposites can do the same job. Hot and cold (a la Aristotle), form and formless(substance, also Aristotle), limited and unlimited (Pythagoras), continuous and discrete (atomists, Parmenides), wet and dry (Aristotle), same and different (Plato), Being and not-being (many), there is even a famous philosophy book called the Raw and the Cooked which does just fine.
Sex is technically mystical, both in act and thought. It involves the joining of opposites (in this case male and female). Sex is therefore not merely philosophical. However, there are more profound things to join than male and female, such as control and freedom, order and chaos. There is more to be gained from joining control and freedom. You learn how to be act and think freely, and maintain control. That is a better and more lasting gain than a sexual orgasm. I feel that people who spend their intellectual lives cultivating the flow of secretions in their nether regions are a loss to society, much like those who spend their time playing Nintendo. I mean sure, play Nintendo, have sex, compete in sports or business, but at least recognize there are higher callings in life that we should aspire toward sometimes.