Why do people hate Cena but love The Rock?

A lot of Professional Wrestling Fans have short memories and I find it amusing. I have a long memory and a lot of the complaints that are leveled at John Cena (He's only knows a few moves. He kisses up to the fans.) are the same complaints that were made about The Rock when he first came to the WWE. Everytime I turn on WWE Classics on Demand and I watch Monday Night Raw from 1998, I hear Rocky Sucks! Chants. I remember going to WWE Shows in the 1990's and hearing people saying The Rock only had 5 moves, when I saw more than 5 moves in just one sequense during any of his matches. That's why I don't give a lot of credence to wrestling fans complaining about a wrestler. They really do have short and convenient memories.