No. Look at it this way. If, during that six-month stretch, the Rock had also been inactive, the WWF would have been fine. HHH/Foley was drawing just fine. The fact is that, at that time, WCW was utter shit and the WWF was the only other option; and at the time the wrestling industry was booming. The WWF could have put out garbage (which most of the Attitude Era was, but that's another subject) and still have carried on strong. They did not need the Rock at all. Thus, he did not carry the company.
On the other hand, the WWF very well could have folded without Stone Cold. If he was never in the picture, I'm not confident that there would be a WWE today.
And with Cena, he has carried the company to whole new international markets. The company is BOOMING right now in foreign markets that are hot about Cena and the rest of the product right now. Since mid-2006, Cena has been the undeniable Ace of the product; without him, a huge chunk of the fanbase would have never been brought it.
The horny teenage girl fanbase?
I think Cena is excellent on the mike, but when it comes to the ring he just doesnt do it for me. I am amazed at his strength and think he is a good role model.
But over all, he's not the best.