Well, everything is bad when treated in the wrong and I couldn't blame OP for saying that because it is probably he has a bad experience with gambling. But he should not say EVERYONE because not all are doing the same with him.
Anyway, we can't please people to see the benefits of gambling, many think it is bad and harmful to us (mentally and financially matter). But for the reason that I gamble just for fun and is able to relieve my stress, I keep doing this. It just needs self-control and it is all okay. Of course, we don't expect to win big but at least we are enjoying our time gambling.
People with a bad experience with something will say it is bad and advise others not to do it. It was only natural that he said that to warn everyone about the impact of gambling. But for those who can still control themselves when gambling, they will still gamble and they will always be careful.
As long as we can use it well and not excessively, no problems will occur. Problems will arise when we go too far in using it and excessive things could be better. And as long as we can use gambling well, just to have fun and fill our free time and don't overdo it, we will be fine. We must be able to control ourselves when gambling so that we don't experience any problems.