Modern day techno-equipped militaries have proven that they aren't good at efficiently fighting guerilla fighters (that is, when politicians are involved). Ukraine is basically fighting as such and that's smart because there's a politician (and KGB spy, not military realist) behind this.
Ukraine are scrappy as fuck and I like it... a lot. Still have a hard time believing they can truly beat Russia back without a western military force injection, but the mix of the "Go Fuck Yourself" on the radio and Ukraine's president not running like a coward are winning hearts and minds.
Interestingly, while essentially nobody powerful (except maybe China... as they feel it out) was supportive of Russia's incursion, it seems Putin has perhaps unexpectedly earned himself the novel threat of being skinned alive in the global geopolitical dance -- and potentially at home. Inasmuch as he is justifying this war with claims of eliminating Nazism, he is being classed in the same group as Hitler. And that won't work out well for him.
I strongly believe the EU/NATO/Biden Admin was surprised Ukraine has lasted this long and actually has been putting the hurt on Russia. That's somewhat understandable considering the vastly uneven odds. But perhaps "The West" has underestimated the strength and passionate influence of the human desire for freedom from aristocracy, tyranny, and indirect democracy (the Russian form). Sadly this is likely because they have spent the past two years trying to strip away freedoms in the name of the illusion of safety. But perhaps this war will remind those in power who they work for. Perhaps this war will finally inform the EU that they cannot have their social safety nets on the backs of the American military's protection.
I'm not sure sanctions are working NOW but if they are left in place after this is all over (not getting my hopes up), they will absolutely destroy Putin's power and severely harm Russia (not without consequence to the rest of the western world, no doubt). Overtly, in Russia, it's not a conspiracy to think that he is killed by his own if he fails (if the cost of this outweighs the benefits, which is more and more likely). And if the poker game is played just right, the west can influence Mother Russia further in the direction of a true Republic, which is what Russia needs, as a necessity for the sanctions to be lifted. I don't think we could sanction China into submission, but Russia isn't manufacturing everything... it's a petro state.