That's the side effect of gambling and no one can skip that until he realizes that he's doing it wrongly. Yes, he's gambling it the wrong way and didn't able to control himself and was able to take a huge loan. $18k is no joke in today's period of time and this money can do a lot of stuff if someone gives me that amount. But can we revert our actions just as this guy? No. But it's not too late for him to re-do his things and has to repay the loan for him to move comfortably whether he wants to gamble again or invest in Bitcoin. We can't direct people's action and correct them or regret from what they've done. It's true that there's a feeling of being able to regret as if we're in their shoes but let them serve the mistake to teach them valuable lessons in life.
Don't know about you but I didn't suffer that consequence that you're talking about gambling because I'm smart, I didn't have to learn those lessons the hard way, more like I've learned them from the people around me that have made that mistake, that's the wisest move which is to learn from the mistakes of others and heed the advice that they've got about those experiences and so you don't have to experience it anymore. Definitely he can do the repayment but to me, depending on where he's from, he's better off defaulting that money in a way that wouldn't land him a jailtime because repayment is going to be a worthless hard work for him, not being able to enjoy the fruits of your labor because you're paying that debt, I guess that's part of the punishment.
Your focus on learning from others' gambling mistakes is smart. There's a fine line between cautious advice and squandered opportunities. Responsible gambling involves planning, risk management, and the excitement of the unknown. A skill that can be improved.
Your friend's debt: default over repayment? A dangerous move. Its hard to struggle to pay off debts, but honesty matters. Repayment restores trust and accountability, not just money. Defaulting may appear easy, but it has legal, moral, and personal ramifications. Gambling is about risk against profit. While learning from others is wise, doing it yourself with control and understanding is invaluable. Balance means understanding when to risk and when to retreat. The actual art of gaming and life.