The people having lost are the people being dead, the families separated and people traumatized. Like in all wars. The victims are mostly the working class.

That said, there are plenty of ways to spin winning and losing for both Ukraine and Russia. Of course for NATO this war war somewhat good, but there can be a couple of things be found that are bad, will not focus on that though.

Having secured the Krim, having secured a Krim land bridge, having ensured a close alignment of Donbas and Luhansk, having secured control over the Sea of Azov and in addition relevant parts of the North Western section of the Black Sea (and with that ensured access to gas and other resources while denying it to Ukraine), having the river as border in the South between the occupied territories and Ukraine, with mined and defended territory near Donetsk Oblast reduced the open flank of Russia (and its Krim) somewhat. This means millions of people who are effectively living on territory controlled by Russia. This also means a propaganda victory for Putin and thus support from some circles of nationalist society in Russia (for which the education in military basics adds something, too).

Hard to call all those things failures. That said during a war of attrition and position war is slow till it isn’t anymore. I am not on the side of Russia, but I can see how stuff could be spun.