It's a ludicrous notion for The Rock, Batista, Cena or Orton to end the streak. It'd result in a huge backlash from fans, other wrestlers, wrestling insiders and damn near everyone else partially because ending the streak is something that won't benefit them to any major degree. Between the four of them, they've won a total of 42 World Championships, they've main evented multiple WrestleMania events, they've each won the Royal Rumble at least once, etc. They've been to the top of the mountain so many times that it could be named after them.
The Rock has been good for business and making money is what any good business is all about. However, it's possible that a lot of fans aren't as excited about The Rock as they once were. Since the post WM Raw last year, the few times his name has been dropped has met with a very mixed reaction. When Hogan dropped his name this past Monday, there was hardly no reaction. Considering the type of response Batista's gotten since his return, it wouldn't surprise me at all if The Rock received a similar welcome if he returned. If he did return, you know he'd be stepping into a prime spot and it's possible that many fans would be resentful because they'd feel the spot should go to someone that's been busting his ass year round. The Rock's a much bigger star than Batista and much more talented overall, but I don't think he'd be as welcomed as he once was.
There's also the strong possibility that The Rock may never wrestle again because the injury he suffered at WrestleMania 29 opened his eyes to what he'd be risking. If he gets hurt again next time around, or gets hurt even worse, it could screw up what's once again become a very lucrative film career. I've read that he makes between $20 and $30 million per film and his movie career has been revitalized over the past several years. If the Hercules movie is a big success this summer, it'll make his film career even bigger and his participation in that movie was at risk for a while after he got hurt. As a result, The Rock may decide that getting in the ring again isn't worth the risk.
If the streak ever comes to an end, in my opinion, it should be ended by someone who'll actually benefit from the rub. The Rock is not someone who'll benefit from it as he's already as big of a star as it's possible to be; he's the ultimate crossover success story in pro wrestling.