It's not luck or
skill, it's skill in dealing with luck. For any individual hand non-head's up, luck is the predominant force. You have to be lucky enough to have a decent hand to play preflop, assuming not insane play. Then you have to be lucky enough to either hit the flop, or have your opponent be weak enough to let a bluff
through. If you want to win a big pot, you have to be lucky enough for both you and the villain to hit the board, with you hitting it better than your opponent, and you have to be lucky enough for your hand to keep holding up. If I flop a royal flush, Phil Ivey couldn't push me off of it, even if he's the best poker player in the world, and if he hits something like quad aces, he's probably going to loose a big pot to me, good chance the size of either my or his stack, depending on which is smaller. My luck beats his skill in that hand. I have no doubt that over a session of many hands
, I would come out ahead of Phil almost never. His skill beats my luck over the course of many hands.
Over a lot of iterations, skill becomes the predominant force. The best players win more than they loose in the long run, and unless you believe that a bunch of random people are magically, consistently luckier than everyone else, the only other explanation is skill.
All "luck" is is when things out of anyone's control go better (or worse in the case of bad luck) than you'd expect. If you understand how probability works, you'll understand that if you repeat a process that includes randomness, good luck and bad luck will happen a lot, and if you repeat it enough, it should eventually even out (though that can take a very long time). A few of the primary skills in poker is understanding how to 1) play profitably based on a good understanding of probability, and 2) manipulate other people's play based on their poor understandings of probability.