The voice thing has always interested me. I've long been aware that women raise the pitch of their voice when talking about men they like. I've annoyed a few friends over the years by bluntly calling them on their attraction to a guy they are telling me a boring story about. It's all very obvious within a couple sentences but you quickly develop a reputation as a mind reader if you do it too often. As to why I call them on it, it's a combination of innate trolling and getting immediately to the point so I don't have to play the role of the mirror person that reflects their conversation back to them as a way of affirming the attraction.
But what I have had difficulty understanding is when men do this, raise
their voice pitch in a sweet and fake kind of way to talk to women. I get the impression they do it to seem like a nice guy, to seem sensitive. It's a huge red flag to me. If I hear any guy putting on that voice I don't trust them at all.