Both, just depends on if he can pull it off or not , Some guys are better off with short hair than they are long, an some guys are opposite. There's honestly not a true right or wrong answer for this question, girls options change all the time. One day they think something then the next thing you know they think the opposite of what they did before. &&&& then again girls are the ones that are meant to have longer hair, guys are meant to have shorter hair, it's like a representation kinda thing ya know haha
I think it depends on what the guy looks like. Some people look better with short hair, others when they have long hair they look like they need a haircut. But what if the guy maybe has a large forehead? Then he maybe needs bangs to cover it, or maybe his head is small? Then he may need an Afro to balance it out. All depends on the guy's looks if you ask me.