Sexual Attraction is pretty much exclusively determined by looks/physical traits.

My argument:

  • Sexual arousal is determined by sexuality. Heterosexual people are aroused by people of the opposite gender, homosexual people are aroused by people of the same gender, bisexual people are aroused by people of both genders, and other sexualities do other things etc.
  • In daily life, we assume someone's biological sex according to secondary sexual characteristics such as: facial hair, facial structure, hair length, body shape, height, voice pitch, etc. We don't determine this according to primary sexual characteristics such as genetalia because you can only see that once you see them naked. In a dating context, you would only see someone naked after you've seen them with clothes on, found them sexually attractive, decided to ask them out, went on a date with them, etc. until you finally decided to have sex and thus see them naked. Sexual attraction came about long before you saw them naked and became aware of their primary sexual characteristics.
  • If we see someone lack too many secondary sexual characteristics of our preffered sex, then we won't percieve them as sexually attractive. For example, if a heterosexual woman met a man who had no facial hair, had long hair, was shorter than her, skinnier than her, had a higher pitched voice than her, had wider hips than her, had narrower shoulders than her, had a rounder face than her, etc, then she's probably not gonna find him sexually attractive. Maybe a bisexual/pansexual man or woman would, or some other sexuality would, but I don't see a heterosexual woman finding him attractive because the man doesn't look like a man. That man's failures in dating isn't gonna be due to not having enough confidence or having a negative attitude, its gonna be due to his appearance/physical traits.
  • The aformentioned man can't compensate for his lack of secondary sexual characteristics through personality. Because personality traits aren't gendered and are therefore unrelated to sexualities. For example, as a heterosexual man, no matter how confident or charismatic my male friends are I won't find them sexually attractive. Charisma or confidence can't turn me bisexual. Sexuality is hard set at birth, it isn't a choice, nor is it malleable. In the same way, heterosexual women aren't going to find the man without any masculine secondary sexual characteristics sexually attractive regardless of confident or charismatic he is.
  • Therefore, the only factor that effects sexual attractiveness is looks, whereas personality traits or charisma or confidence or "game" or pick-up strategies aren't factors in the equation at all.

Caveats:

  • No, I'm not saying men or women need to have 100% of all possible secondary sexual characteristics to be considered sexually attractive. For example, women can still consider a short man, or a skinny man, or a man with a weak jaw and chin sexually attractive as long as he has plenty of other secondary sexual characteristics to compensate. Even the effeminate men that women claim to find attractive are still easily identifiable as men. Timothee Chamalat is often used as an example of an effeminate man that lots of women like, but whilst he looks a little effeminate he's very obviously a man - he's 5 foot 10, he has broad shoulders, narrow hips and he has an incredibly strong, defined and square jawline - he has a lot of masculine secondary sexual characteristics.
  • Don't conflate finding someone sexually attractive and wanting to date someone. Dating and romantic relationships as a whole involve a lot more than having sex, such as having a conversation with someone and when it comes to romance going on the journey of life with someone. In that sense, dating and romance requires two things: sexual attraction and platonic attraction. Whilst sexual attraction is entirely determined by physical appearance as I've previous described, platonic attraction is determined by personality and isn't related to gender or sexuality. Which means that even if I find a woman sexually attractive, I might not want to date her if she isn't able to conjure platonic attraction via having a pleasant personality. And I also just feel like the feeling of "romance" is a chemical reaction of fusing sexual and platonic attraction together, creating an entirely new feeling. But for the chemical reaction to take place, both constituents need to be there, you can't just have one or the other, and neither can compensate for the other. Attraction doesn't work in a way that allows one to compensate for the other. There's a specific threshold you have to meet for both.