The thing is that majority of people who borrows thinks they could pay it back until something bad happens. I guess we have to be more specific here that a person could take a loan to invest in crypto but it has to be within his earning capacity. Taking $100K when you're only earning roughly $3K (gross) a month for example.
The problem about money borrowing isn't the main issue, it's about the size. There are kind of money that you are going to borrow and you will be able to pay back no matter the unexpected problems that will arise later. If you have a plan to borrow money, try as much as possible to borrow 5-10% of what you earned, so you can find a way to squeeze in paying back the money.
Some people will borrow 3x of what they make and plans to pay in batch payment but the challenge about this is that you don't know what make come up later, you know life is full of ups and down, you don't know what can come next, this is why you should plan but add worse scenarios.