He'd be 27 for the Olympics, pretty old but still possible. Fumie is 28 right now...
Not that old. If Kevin van den Perren (who is older), can put down a jumping clinic after a hip surgery, certainly Evgheni will be able to do it as well. If you browse some videos of his recent shows, he didn't lose his lightness in his jumping and probably with little preparation he is able to do most of them.
So he could return anytime and pull together a 7-8 triple program. The big question is , would he be able to adjust to the new COP requirements, which are much more demanding than in 2006, crossovers around the rink and some average spins with his armflaiiling generic footwork won't be enough for the big reward and I don't think he is interested in anything but gold.