Sorry, I've seen too many folks who have turned their backs on Russia, permanently, at the insistence of their own parents. But in a way, Putin's idea isn't all that ridiculous. One, those folks are out there b/c they were told or lured to go in order to Russify their neighbors -- a fact, combined with Soviet law, that has done nothing to ingratiate those folks to their neighbors.
And Russia is indeed demographically imploding. But that's mostly because conditions at home are so intolerable. I tend to agree with Andy Blair that Russia right now is closest to a Lakedaimonian Oligarchy. If Putin wants to succeed, he's going to have to start using Russian oil and natural gas wealth to improve the lives of its NeoHelots... because otherwise, given a choice between being roundly scorned and resented, but paid regularly, where they live now, and uprooting themselves to face all the horrors that make up domestic life in Russia right now... not a chance.
Much of this depends squarely on Putin. Russia can survive, and be a powerful player in the following century, if he opens up and reverses some of his oligarchic trends. Even some of the minorities that are also going extinct, such as the Mari, would likely be overall regime-supporters were that to happen.
But if he fails to do so, no amount of energy revenue will save Russia from becoming a colder version of Libya -- well-funded (for those who matter), inhospitable to the average political subject, and too underpopulated to have any meaningful effect upon its neighbors.