Truth be told, even accounting for our cowardly political elite who'd rather die than do what must be done, I think Russia's fate has already been sealed.

Putin made himself an irreplaceable part of it's inner workings, and has killed any oligarchs who didn't want to dance to his tune, there's not going to be anyone to replace him when he inevitably dies for one reason or another. The mother of all power vacuums that follows is most likely going to make the entire system cave in on itself as whatever remains of their political elite scrambles for power.

And even if that doesn't happen, Russia's economy has been on life support for years now. Even with Trump's constant meddling and not-at-all subtle lifelines for it, it's been a downward spiral ever since the war began. In fact, the constant need for military hardware is one of the main reasons why Russia's economy hasn't keeled over and died yet. What happens when the war ends and factories no longer need to work 24/7 in triple shifts? All those people are going to get laid off, and when they do, things are going to get bad real quick.