Coin flipping has so much to do with luck and with little or no skill at all whereas in day trading you can't just open a position to trade hinging on luck there must be an applied skills from a long time built technique.
I have learnt a number of lessons from my losses in gambling but I can't say I can depend and work with the experiences of those losses to make profit in subsequent bets but for trade the more experience and knowledge you possess the more chances you have of making profitable trades without having to be lucky at it.
Exactly, that's their difference. Experience in lauck based games (or in coin flip specifically) doesn't increase your chances to profit the next time you gamble again. Because there's no skills that can help you to win, thus regardless of what you do the result will still depend on your luck.
While on trading, experience can help yourself to improve, this can increase the possibility to profit next time since you gained knowledge already from your past experiences. Although it is also risky just like gambling, but the trading doesn't solely relying on luck. The more experience you have, means you already learned something, it could be another knowledge or strategy.