Not sure about this interpretation.
Remember MacArthur's famous words during the Korean War? "We'll be home by Christmas".
The US and her 16 allies had already taken over the entire Korean peninsula, until the Chinese intervention. In which they were forced into the longest retreat in their own military history. All we wanted was a buffer zone, and we got it.
Unfortunately we will have to agree to disagree here.
For us, the war started when North Korea invaded South Korea, and we pushed them back but failed to topple North Korea. We failed to integrate North Korea with South Korea, but South Korea was defended.
For you, it started when China entered the war, and you managed to maintain your buffer state but failed to push us off the peninsula (and no it wasn't for lack of trying).
We are simply at a disconnect, because to us the war wasn't all about China, even if to you it was all about the US.
All of this is beside the actual point of my post though. JHungary answered it in good order with his own belief, but do you think China today might have been better served by a United Korea under a 'South Korean' style government with potentially no real reason for a US troop presence, and because of this lack of threat and history, one that might view relations with the US and relations with China differently?
Today, North Korea is still here and setting off nukes, bombing South Korean warships and shelling their civilians. How exactly can anyone call that a "victory"? Maybe it was a victory for the Fat Kims.
When I say victory i mean an objective victory. Today's state could be argued as an 'objective victory' for both China and the US, wherein both accomplished their primary reasons for the conflict but failed to follow through with the most optimum outcome for their respective interests.
Geopolitically I'd say it hasn't turned out very good for China though. North Korea has turned out to be a huge headache for China on the Geopolitical stage, and just another reason for US presence in Asia.