It's more fun having him as everyman in the 25th Century. It is better to concentrate on what this planet will be like 500 years from now, and not be dealing with little aliens in space and all that related stuff.
“Look, I play all these tough guys and thugs and strong, complex characters. In real life, I am a cringing, neurotic Jewish mess. Can't I for once play that on stage?”
“I've done the calculation and your chances of winning the lottery are identical whether you play or not.”