I don't know...while I do have a feeling Russia may win the war, I don't think it would NOT be bittersweet for Putin, or Putinhead as I'd like to call him. If I recall correctly, he is using a lot of the population of his country for soldiers. While Russia's population IS big, the decrease in the population at whatever significant level may not be a good thing for Russia in a way. I mean, Putinhead (that nickname is a pun of Puddin' Head, by the way) has already started resorting to using prisoners and has used mercenaries as soldiers, and is drafting people in Russia while giving them little training, too, if I heard correctly. It also does not help that Putinhead is someone who is not a good strategist and things have not gone his way all the time in this war, as @The Grand Nudger said.
While this may not lead to the Russian populace overthrowing Putinhead. I still think this war, based on however longer it may last, could have more economic and maybe political negative results. I am not sure what, to be honest, but I do think there will be plenty of bittersweet-ness for Russia after the war regardless of if they win. I mean, I have my doubts on Ukraine winning, but even if Ukraine's damages are worse than Russia's, I am more worried about the negative results for Russia more than wanting Ukraine to win.
While this may not lead to the Russian populace overthrowing Putinhead. I still think this war, based on however longer it may last, could have more economic and maybe political negative results. I am not sure what, to be honest, but I do think there will be plenty of bittersweet-ness for Russia after the war regardless of if they win. I mean, I have my doubts on Ukraine winning, but even if Ukraine's damages are worse than Russia's, I am more worried about the negative results for Russia more than wanting Ukraine to win.