I don't think there is anyone that will say that trading is completely bad because it isn't and there are people making a decent living from trading. What seems to make trading bad is the attitude of people towards trading. If you have tried trading before, you will agree with me that there is this hype and tendency to think that making money could be easy and fast from trading. This is usually the source of problem for people and the reason you see many people fail in trading. When people are so hyped and focused on the money, they tend to ignore the need to control the risk, therefore they go all in and often harm their finances so badly.
The only trading strategy which have potential to work in an unpredictable market is long term trading, which involved the trader holding for a long time period, up to few years... That is why patience is needed. On the other hand, for daily traders there aren't any assurances they are going to make guaranteed profit from this activity in a daily basis, therefore to rely a living from trading is too risky due to market's conditions.
Using the long term strategy to hodl your coins, it will give you reasonable profits than those that is using short term strategy in their hodling because it hard for the short term hodlers to earn big profits from their trading than long term traders. But there are some day traders that use to earn profits from their daily trading, but some of them are not satisfied with what they are earning from their daily trading, but the reason why they are still using the day trading is because they don't have the money to go into the long term trading because it requires money and patient in their hodling when waiting for the price of their choice to occur in the market before they can trade to earn profits.
And doesn't matter how professional and skilled the individual is on trading matters, he still can't forecast the next movement of crypto market accurately.
Crypto price is unpredictable no matter how good you are in the crypto industry, but if you can apply patient in your hodling, I guess you will get what you want from the market or you want your target to come to pass before you can trade to earn your favorite profits, pay attention to your patient because there is no way you can hodl for long for your prediction not come to past in the market.