Yours is a comfortable opinion. From an accounting standpoint, "Luck" is a zero sum statistic. One side is as unlucky as the other is lucky. I would never consider (or write about) a betting system that relied upon "being lucky." It would not have an accounting base. I know of no good method of measurement. Wins and losses are sporadic. There is no good reason to think that "luck" as a variable force exists.
There are too many documented studies of "paranormal" events to discount that some people sometimes exhibit knowledge or abilities that are beyond human kin. I don't think "positive psychology" has any effect on a roulette wheel, dice or a horse. I am qualified to make the statement. I hold a B.S. (psychology) and an M.S. (psychology). I think it may be possible that people develop latent abilities. Your expression: "Just hard work and experience." is a case in point. You describe how to improve an ability. Accounting readily accepts that hypothesis. My PhD (business administration) accepts that hypothesis.
We are still stuck with "It takes one white crow to disprove the hypothesis that all crows are black." I have written the four booklets mentioned above and they are now (I think) available on JVZoo and ClickBank. I would make them available for free but because of affiliate costs, $2.95 is as close to free as I can make them. They describe how to develop "Precall" and recognize is (via dowsing) for specific games. They do not "open the skies and let wonders in." They describe how one can develop and test for themselves. I cannot predict that anyone will be successful but I can predict that unless one considers and idea and tests for themselves, they will never know for sure.
As a side note, I doubt the exercises described would have value to either you or myself. It seems that rational thinking inhibits development of latent abilities (if they exist at all). I have no disagreement with the statements that you raised. Your approach is that which I have followed all of my life. "You and I think, we do not believe" or at least not until someone hits us over the head with a two by four.