When I said closure, I meant for fans. Yes, there was a regen scene, but with a 50th anniversary, if he'd done it, '3 Drs'/'5 Drs' style, people would just shut up, I'm pretty certain of that.
That said, once the 50th is passed, he probably won't be asked again.
An actor does owe something to the fans, but by the same token, they can set their own course, with all the rewards and risks of that. I'm a little disappointed CE didn't want to come back, but that's fine and I wish him well.