Sorry, I think you are wrong.
I admit the case where a woman was attractive who could have and maintain a friendship are few and far between - IT DOES HAPPEN.
I knew one guy that we were initially attracted but nothing ever happend - we are talking never even a kiss and I slept in that man's apartment. We were upfront about our feelings for each other, (yes we were MUTUALLY ATTRACTED) but we never crossed that line. There was ample opportunity for us both and we never crossed the line.
Another man took me in when I had no place to live, no friends that could help, I had no money, no family close by to help me, no food, couldn't speak the language. He met when when I was STRIPPING... not "dancing" we are talking STRIPPING. He met me in the club. When he found out the situation HE IMMEDIATELY INSISTED ON HELPING ME. I had very few options and I trusted him... as he trusted me to live in HIS APARTMENT. This man had an important position where his rank was socially high and earned A LOT of money. He was much bigger than me and was a very attractive man who could have easily either physically overpowerd me (the apartment was a studio so we slept in the same bed) or beguiled me with his charm. HE DID NEITHER.
I stayed with him for two weeks until I was able to find a place of my own.
We have had intermittent phone contact (He travels a lot and I am no longer geographically close). But even if I never see or hear from him again - I will consider him a friend.
Never has a man showed me such kindness.... NEVER.
He is one of the people that is helping me to "undo" all the of the negative shit that has been heaped on me since I was a very young child.
So I have to answer that YES - a man and a woman can MOST DEFINITELY be friends irrespective of the fact of sexual attraction.