Right now, Russia looks like it wants to fight to the last Ukrainian, Europe wants to fight to the last Ukrainian, and Ukraine wants to fight to the last Ukrainian. Odds are good that everybody is going to get what they want.
The war will likely end with Russia badly bruised and battered for a generation, Europe on the verge of economic collapse, and Ukraine with a lot less Ukrainians. It's hard to say who is the winner because everyone looks like a loser. This entire war has been a failure for all parties and a giant waste of blood and treasure, especially for Russia who monumentally fucked up the opening of this war and it's now paying the price in a retarded slow grinding war of human and industrial attrition.
I am not sure the conclusion is quite so obvious.
With nearly five years having passed since the start of the war—which evolved into a high-intensity war of attrition driven by NATO to maximize economic, military, social, and political exhaustion—we can offer a critical and objective assessment of the effects the Russo-Ukrainian War has had on Russia, beyond its deep entanglement in a protracted conflict and a fierce confrontation with the West that has brought about seismic shifts within Russian society and institutions.
1) Negative consequences for the Russian Federation stemming from the war in Ukraine
a) Massive human losses > short-term effect
b) Destruction of and damage to civilian infrastructure > short-term effect
c) Fuel and energy issues > short-term effect
d) Digital isolation and Internet degradation > medium-term effect
e) Unprecedented international sanctions > medium-term effect
f) Decline in living standards and inflation > short-term effect
g) Flight and "brain drain" > long-term effect
h) Growing dependence on China > long-term effect
i) Militarization and domestic repression > medium-term effect
j) NATO expansion in its strategic periphery and escalating confrontation directed against it > long-term effect
2) Positive aspects for Russia resulting from the war in Ukraine
a) Growth in domestic production driven by import substitution across numerous economic sectors > medium-term effect
b) Development of the military-industrial complex > medium-term effect
c) Formation of alternative diplomatic alliances > long-term effect
d) Purging of corrupt military personnel > short-term effect
e) Forced acquisition of unique experience and stress-testing of the country's systems > long-term effect
f) Control over destroyed cities > long-term effect
Regardless of the war's outcome, negative effects predominate in the short and medium term, whereas potential positive gains will only materialize given appropriate policies and long-term stability.