IMO gambling is gambling as long as it's purely depending on luck and no support for it on other aspects "knowing methods of trading, best methods and ways to earn, specific market analysis", if the trader doesn't know these then it's merely gambling.
You are right. When trading, you have to do research and analysis how things will change before you do your trading. In this way, you will be able to reduce your risk of losing and make intelligent action. However, if you are blindly trading than there is no different from gambling where you purely rely on luck.