Those people who think that trading is gambling are people who go into trading and approach the market with the mindset of a gambler. They don't follow the rules of trading and they jump in and jump out which is not so. Before you should take any single trade you must have a proper plan, that is your entry and exiting point, Take profit and stop loss, and must have your terms and conditions of taking a trade met and never be in a hurry, trading is a waiting game, when you hurriedly enter the market, most likely you would either hurry out with a lose and that is not how to approach the market.
People think that trading is the same as gambling, so we assume that when he enters the market, he is not equipped with basic trading knowledge, he will think that way, maybe it is more appropriate when he buys shitcoin for trading and hopes to go up 10x if he doesn't make it then say this is the same as gambling, so people who don't understand trading fully.
Trading must be equipped with a variety of ways including fundamentals, technical analysis, candles, market sentiment, patterns that are needed including risk management because this is most important in a trade, if you do not apply the above then we will often experience losses because we ignore the skills needed.
The point is that trading is not gambling, but there are certain ways that you must master to take advantage.