If you were able to convert $20 into $320 with a very low leverage, then that is very good trading and not gambling, but if gained that much profit and lost so much also from using a very high leverage then what you've done is no different from gambling. There is a very high volatility with perps, if you must be profitable trading there, you must learn to measure your risk, practice risk management which includes not using a high leverage. When you begin to follow proper trading principles and steps, then trading will feel more like trading than gambling.
Based on the image he is not using low leverage but 25x to 40x.
The problem is he is too greedy; he already made $320, but still he didn't take the profit that's a total gamble. If you actually didn't know what you were doing, if you compared it to the casino, you would still need to wager before you could withdraw, but that's a clean $320 minus trading fees and fund fees. It's already 16x the amount he risks.
@OP, it's still different from the casino. Actually, you can't just immediately make $320 in the casino unless you are lucky. Next time, prioritize your profit over letting the market take your profit.