Trading have a lot of similarity with gambling with the difference almost insignificant. Your distinction id primarily base on the fact that you see trading as skill whereas gambling as entirely a thing of luck and I want to fault such line of thought because gambling too require skills and those who have the right skills are able to win gambling much more than those who approach it like it were just a thing of luck. On the basis of skill and emotions, trading and gambling are completely similar just that the risk make them a little different as the risk of trading is more controllable than that of gambling.
Seriously I feel like people who says this have no idea of what trading is... It's nothing like gambling mate don't compare both.. gambling requires no skill, if you understand the games just dive in and do your thing if you are lucky you win. Not everyone knows how to trade the financial market, but any one can gamble so long they have enough money. Been trading for long and from my years of experience, you cannot trade without having enough knowledge of the market. Those who copy signals and make money are not traders.. so trading is no way similar to gambling.
There is an undeniable need for experience in trading in the financial markets and for this you need to focus on trading strategies along with money. To win in gambling you need to have floating cash regardless of luck which is the skill of achieving goals through patience. I say that lack of experience is more responsible for losing money in gambling or trading in the market. Being lucky can bring you victory in both cases, along with being a good entrepreneur by systematically converting your feelings into action. I agree with you that the process of making money by copying signals is not a business sign. A trader has to be aware of his intuition and try to gain profit by considering the surrounding situation. This method allows him to be skilled in making money and finally he becomes a strategic investor.