Ukraine

Recognizing this window of opportunity and the vulnerability of the Russians, Ukrainian forces acted decisively. With Russian reserves either dead in the fields or stationed too far to provide timely reinforcements, Ukraine pressed its advantage, launching coordinated air, drone, and HIMARS missile strikes against known Russian troop concentrations in Kindrativka. Ukrainian drones methodically hunted down and eliminated Russian infantry clusters, while precise HIMARS strikes obliterated remaining fortifications and munitions stores with devastating effect. Airstrikes with AASM Hammer bombs ensured no immediate reinforcements could move forward safely, effectively neutralizing major resistance within Kindrativka itself and limiting the possibility of surviving Russian troops finding cover within the ruins.

This is what decisively losing a war sounds like.

Notice, no matter what Russia claims about how warfare is changed and they don't need armor just dirtbikes and atvs... the reason this counterattack was so costly for Russia was precisely because the infantry essentially had no access to transportation they could safely use in groups to quickly reposition to counter Ukrainian maneuvers. This is why mechanization is such an advantage in modern warfare and how it is almost shocking the degree to which Russia seems to be ignoring that reality.

Ukraine significantly disrupted Russian logistics and troop rotations, effectively sabotaging Russia’s goal of establishing drone and artillery fire control over the regional capital, Sumy.

I don't see how adding more foreign troops who probably haven't even trained with the random Russian troops they are being thrown together with into this mix is going to change things, 30,000 soldiers from any nation is nothing to dismiss especially from a nation with a large military like North Korea but I don't think it really changes the calculus. I especially don't think Russia's foreign allies are going to be happy when images and video of their long range expensive artillery systems getting repeatedly annihilated by Ukrainian drones and counter battery fire goes viral on the internet...

If Putin does not back down and agree to some sort of exit or ceasefire from this war we can only hope that Ukraine can continue to exploit this severe limitation to the Russian military in order to encircle large numbers of troops and get them to surrender without countless Ukrainians having to die in an endless battle of head on attrition that has so far typified most of the war.