And of course if there's a marked technological advantage it will trump pilot skill. But such a large disparity in technological capability doesn't happen all that often.
And that's why I brought up the technological levels of the hypothetical participants. Depending on which countries are involved, there are different answers to the question of whether one side or another has such a large technological advantage.
NK has about twice as many fighters as SK, in an oddly wide variety of models up to some Mig 29s but all the way down from there to barely-post-WWII models equivalent to a North American Sabre (P-86/F-86) or Mig 15, planes which, even if they weren't getting shot at at all, would still never even get a chance to try to shoot at any of the other planes I'll be talking about here anyway just because of differences in speed and such. Compared to SK, that leaves their average not very good, their really good ones outnumbered, and their training process and tactical planning considerations a scattered mess.
SK does have a bunch of F-4s and F-5s, models which the USA used as far back as the Vietnam war, but nothing older, and even the USA didn't retire its last F-4s until the 1990s. Also, SK's F-5s are about to be retired in favor of a cheap but more modern locally-made lightweight, and about half of their total force is already F-16s and F-15s, more of which are still on the way. With this kind of technological edge, SK couldn't lose if all of their pilots flew drunk.
SK's better Air Force then neutralizes NK's size advantage on the ground by hitting ground forces from the air (including not just blowing up the vehicles or roads but also hitting infantry on foot with anti-personnel weapons like cluster bombs).
But that's all if the war remains entirely Korean. I don't expect China or Russia to get involved at first because they don't have a lot of stake in NK. But if the USA gives in to temptation to help SK make it easier and faster, or even if one American base over there somehow gets involved without planning or trying to, then the two Asian heavyweights will want to counter the American interference. (This gives NK an incentive to attack Americans just to try to get the USA and its adversaries involved so it doesn't have to fight SK alone.)
And that tips the technological comparison back the other way, at least for now. Those two countries have (and can still produce) a much larger number of a mix of Mig and Sukhoi fighters with model numbers in the upper 20s and lower 30s, plus Chengdu J-10s. All of those planes are at least rivals to our "teen" planes that are currently based there, and some are distinctly a step above. And even if you figure our pilots are better than the Chinese and Russian pros, you also have to consider how many can be sent and how much support infrastructure there is nearby: for us it's halfway around the world, but for them, especially China, the whole thing is essentially local. That not only helps them use their jets more effectively but also means they can send ground stuff on the ground. So if China (or Russia) fights, or even sends their planes (and/or other hardware) for NK to use, there's nothing we could do for SK for now. (Same as Taiwan.) The only way we could have a chance would require large numbers of F-22s and F-35s and the base capacity to operate large numbers of them over there, which isn't going to happen soon.