Am I a bad person?

When I first started dating my boyfriend, his hair was like sitting above his shoulders and it was really good on him and I loved it! He's trimmed it up a lot, but he's been growing it out and now it's a lot longer and I don't like it.. I still love him and I'm still attracted to him, but I really don't like his long hair but he loves it. I've asked him if he would cut it before, but he said no he likes it so I'm not gonna ask him again because I'm not that type of person to try to change him because I don't like it. I also joke around a lot about cutting it off in his sleep and he knows those are jokes, he makes jokes about cutting mine off too when I say it lol. I love him, but am I a bad person for not finding him as attractive with the long hair..? I saw a post on here about a girl coloring her hair gray and her boyfriend didn't like it, and all of the comments were like "fuck him if he doesn't like it!" and stuff like that, and it made me feel bad for not liking my boyfriends hair too...