These people should seek financial advice. While some people may make lots of money and are able to pay back their debts, am sure a lot screw up in the market and end up being bankrupt. Only invest what you can afford to lose.
You are right, its a good advice, but some people put last hopes in bitcoin and in some way I admire them. You need to be brave and risk sometimes, people think that with loans from the bank they can double or triple their money and to have to return, that is not bad strategy but bitcoin price can go up
slowly and that is probably not the speed they wish to see. Bitcoin will rise, but for that we need to wait, this price now didn`t come from yesterday its something that is build for 9 years.