It's more exciting because when they have sex it actually looks like they are having sex, and it's akward and weird for 2 guys to be all intimate and stuff but it's not that weird for 2 girls to start hugging and holding their hands in public either. And plus it's more entertaining to see guys acting all weird like that too! (｡>﹏<｡)
Guess you're right!(▰˘◡˘▰)
It's just a matter of personal preference. Some people like yaoi, some people like yuri, some people like hetero stuff.
Why do yaois is more exciting than yuris lol