John Cena made an appearance at BookCon '19 and spoke with the audience and during a Q&A a fan asked who he thought might be "the next John Cena" and he said:

“I think the dynamics of the program is changing. For the longest time, if you considered WWE a band, there’s been one front person of the band,” he replied. “I think that dynamic is changing. It is because the audience is too diverse. I think older males are watching it, younger kids are watching it, females are watching it. The audience is so diverse, so with a diverse audience it’s tough to universally please someone.” 

He went on to say:

“I don’t think there’s a universal figure that will lead the company forward,” he added. “I think as the company grows, and especially expands globally, you’re gonna have like a ‘Super Friends’ of the WWE. Which is like people who are essentially fighting for equal share of popularity. I think the band, essentially, will have ten lead singers of every different race, creed, color, sex, ethnicity.”

Check out Cena's full commentary below: