Shatner, personally, is OK he isn't in the new film. Shatner is happy the franchise is succeeding. Shatner didn't watch Star Trek much either, now you mention it. Shatner is perfectly comfortable no longer being Captain Kirk. Shatner knows exactly who he is: Shatner.
Shatner didn't always know he was Shatner. He described his epiphany to US talk show host Conan O'Brien about a decade ago. Everyone at Star Trek conventions was always talking about "Shatner this" and "Shatner that", Shatner recounted. They were going on as if Kirk/Shatner was a hero with magic powers, some sort of binary god. Who WAS this mythical figure, this "Shatner", Shatner wondered. Then, he said, it dawned on him. HE WAS SHATNER.
From that moment on, Shatner has been Shatner as intensely as any celebrity has ever inhabited a personality. He is one of the few famous people to embrace the fact that his image is nothing more than a plaything of the public, a sort of reality TV star before the genre existed.
Howard Stern gets it right, too!
Bill quietly and firmly reduces a director to jell-o