I love it, myself, I love all hair lengths. Most of the females I have been with have had short hair, actually.
A good analogy is, guys with long hair. Back in high school, a lot of my friends, and me, used to have long hair. And, one time, these couple girls were really ripping into us for it, making a big deal about it, saying it was disgusting and demanding we answer why. After her performance was over, one of her friends stepped in and said 'Look at it this way, it's like when girls can have short hair - these guys have long hair.' The girl had no counterargument, and left, disgruntled.
Theres no logic in it, but it's 'normal' and people are used to normal. Ever since WWI, guys have had buzz-cuts and crew-cuts and whatever else, short cuts, and ever since... Christianity, girls have had long hair. And, when people started to wear long hair or short hair irrespective of their gender designation, it REALLY shocked people. In the 60s there used to be this thing called the 'Freak Scene', and it was just a bunch of people who dressed up in all kinds of fancy clothes that weren't the standard suits and frocks, and they had all kinds of different hairstyles, and they'd walk around the strip having the good time. After a few months, the shop owners called the police on them 'cos they were bad for business. They were arrested - for walking around and looking different. There used to be front-page spreads on magazines about 'unisex haircuts'. And, bob cuts and things were really shocking, on girls. It all eventually took off though, and penetrated mainstream culture.
It quickly fell out, however, after some very strong-arm 90s reactionism and the development of the National Front, and Bullyboys in the 80s, etc. etc., whatever. However it worked out, long hair on boys and short hair on girls speedily fell out of acceptability in Western Culture. Girls with long hair is more okay now, boys with long hair is staaaaarting to be okay, both can result in anger and even violence and neither are usually attractive to the opposite gender.
I don't know why, but, there's a timeline...