That means he's a failure as a heel. What kind of a heel that gets cheered. You think all Cena haters hate him because he's a face, no because he sucks in many ways, and others hate him because of his character, so don't think he will have them all. I will always hate him because of the fact he's over pushed and gets way to much credit for everything.
If you cheer the heels, that means you're entertained by them, especially when it's Cena who so many fans hate him, his job is to entertain the fans at live shows or at home, as long as he brings the rating(which I'm sure if he turns heel the ratings go up)and reaction, he's doing his job.
And with all due respect, who gives a shit if you hate him or not? it's not like you're someone important.