Trading becomes gambling when someone who trades does not have knowledge about it and keeps on losing money. That means he is gambling with his money, but some people confidently compare these two things together, and I think they are not the same. However, the practices that can lead trading to gambling is when a trader keeps losing money and refuses to find a way to sort his problem out because when you lose too much and you are not making money out trading, that is gambling.
Well, I believe that those who compare trading to gambling lack knowledge of crypto trading, because if they did, they would not compare it to gambling. Those who compare trading with gambling, in my opinion, are those who invest for the short term, otherwise, I do not believe people who have held for a long time would compare trading to gambling. However, I'm wondering how some people compare this because no one can predict the price of Bitcoin, and no one can suggest what the Bitcoin price will be in the future, whereas anyone can predict the outcome of a game or any other gambling they risk their money on.