No question they are hurting Russia.
They have gone to rationing.
Russia has won several wars due to the severe winter harming its enemies. Ukraine is turning that against Russia, creating shortages in fuel as they go into winter.
Perhaps the Ukes can use their homegrown and obtained arms such as drones to balance their disadvantage in manpower demographics long enough for Russia to be unwilling to carry on further with the invasion?
You've got to be kidding.