I think it’d be horrible to give up food, sex, exercise, and the rest of our bodily experience
Then don't. Does it not count if it's virtual? Even if you're dead set on a physical body, why do you care whether the brain that's controlling it is made of meat or silicon?
Perhaps you could hibernate for fifty years at a time
Why would you do that? That's fifty years that you're not living. If you do that after each year, you'll only live a fiftieth as long. Also, there's the problem if everyone does that: https://xkcd.com/989/
Why would you do that?
I think Rosenfelder's idea is that if neuroplasticity turns out to be an insurmountable problem, you could do this to get a taste of the future while you're still mentally young enough to appreciate it.
Death, long lives, uploading
Mark Rosenfelder (aka zompist, of language construction kit fame) writes about the advantages and drawbacks of mortality and its alternatives, in fiction and real life. Rosenfelder, as an author, clearly takes Fun Theory very seriously. After discussing the mental and physical decline that age usually entail, he assumes that the most difficult to surmount of these problems will be the loss of mental flexibility and tolerance of novelty. He then uses this obstacle to offer interesting fun-theoretic arguments against uploading and cryonics:
And how he addressed the issue in his own far-future conworld: