Russia will collapse sooner or later, it's just a matter of time.
The West is supplying Ukraine with everything they need and won't suddenly stop. Russia on the other hand is only supported by third world backwards countries like themselves.
Another thing is the Ukrainians are fighting for their independence and liberation, Russia is fighting a meaningless war. It will only be so long before the cracks start to appear and the Russian population want the war to end.
The war will probably not be over this year or the next, but Russia won't be able to sustain a war like this for a whole decade, just can't see that.
Just for comparison - in less than 1 year in Ukraine they lost way more soldiers than they did in a whole decade in Afghanistan. And Afghanistan was one big slump for them. And probably another reason the Soviet Union collapsed when it did.
Russia has always lied and downplayed their casualties and how grim their situation was/is. We saw this countless of times during WW2 when they were on the brink of defeat against the Germans, some of the archives about their role in WW2 and their dire situation in 1941 and 1942 are still closed. Russia has this time bitten of more than they chew and it will bring their downfall.
When Russia realised they lost and wants the war to end I hope the West won't be lenient on them. Some would say it's a Versailles 2.0, but these orcs needs to be put in their place for good and move on to the 21st century. It's about time Russia steps out of the middle ages.