Your belief that sexism in tech is not really sexism and just isolated incidents strikes me as very odd. You analogy to men in bars is completely unrelated and completely not analogous. I'm an attorney and a your whole argument about rude behavior being illegal, well, I would like to see that hold up in court. Proving any type of discrimination is very difficult.
As an attorney, you know that there is an enormous gulf between "what is illegal" and "what will hold up court."
As for it being "systematic" -- how many stories of rude and raunchy VCs would it take? Infinity and beyond!
A thing is not "systematic" unless a bunch of people get together and decide to do it together, intentionally -- and with a process. Otherwise it is merely "widespread" -- just like rude men with poor social skills hitting on women is wide spread in many, many situations that do not involve VC.
Straw man, my friend. They are nothing alike.
I have run into many rude men at bars when attempting to buy drinks. Some have even butted in while I was dancing with another woman. I guess it's time to write an expose entitled "Sexism in the Beer Drinking Industry."