I stopped watching wrestling about 6 years ago or so, around the time Cena came in. I remember what a pussiey he was, but then he was amazing. Why is he so hated now?

Cena has been in WWE for almost 10 years! He's been annoying everyone that doesn't eat fruity pebbles for the last 7 years. Same Old Same Old doesn't even cut it he's so stale. In fact he's so stale he should be dust.

Did the hate for him start when the Rock came back? Or was this building before then?

Hated since 06.

You, personally? Or the whole fanbase? I remember he was pretty popular in 06, as was batista, both of them were on the wwe game cover

I've always hated him. I think the boos started in 06, though.

I loved his rivalry with Edge, tbh. That and when he won the title off JBL were his only good moments imo.

Agreed.

Last night was his Rock-WM19 moment, it's not going to get any bigger, any more furfilling for him than that image of The Rock's admiration in his right hand and the WWE Championship in his left. That is the grandest height he'll ever accomplish - from the characters prospective that moment would rank higher than if he was to end the streak (which could even factor into any Taker match at WM in the future - he's the only wrestler who doesn't "need" to beat Taker).

From a creative standpoint, John Cena the fictional character has reached nirvana - he's completed

Hopefully he retires tonight.

That would be fantastic.