i really doubt that as casinos are made to make people loose their money and make profit out of that, in my opinion you have to be really lucky to win in a long run
Not only luck is needed, it is welcome, but there are people with great math skills.
Great match skills are important. A good memory is also very important. If you can remember all the cards in Balckjack, and analyze the situation properly, when you have bad luck, lose small, when you have good luck, win big. You can win the game in long term.
However, not many of us have this skill.
yeas, winners are lucky and they have very high IQ so that they can easily remember and count cards, if they follow the correct strategies, they will have positive expect return in the long term, but only 10% people are big winners in gambling world.