It also depends on the responsibilities someone has. I just read again about taking out a loan to buy BTC. Honestly, if it is the year 2014, someone has little to no responsibilities, no family to feed and is at a young age and not exaggerating with the loan amount, I think it could be a risk that is worth taking. I have been reading some wild posts here in regards to financing BTC investments, like selling the wife's jewelry and stuff. But if someone decided to take out a moderate loan after crunching some numbers, knowing that if it goes wrong life would still go on quite comfortable, then why not go for it? I know people who have invested so much time into understanding BTC back at the time and if they came up with a well-considered approach to build their portfolio, loan money can be a component if someone understands the implications.
I am definitely not against loans, when it comes to business or investment projects. If someone has a prosperous plan and know how to make more money out of given, than a loan could be very effective instrument. Moreover, big estates are made with the usage of someone else`s money. It is normal situation and most of the people who are willing to achieve something take that risk.
We have to be responsible in everything we do and there is a reason why experts always warn that we should not invest "the amount that we can't afford to lose" in any asset. I don't see a loan as part of the money we can afford to lose, so in practice, I do not see it as a good choice when it comes to investments. Although I buy your idea and someone like me will opt for the loan, only that we know the risk we are taking and we are in for it with a strong mindset. This might not be the best but the more your risks, the more you gain. At times, if you wait too long for you to gather money to invest correctly, it might be too late at that time. So, I do not see a choice in this for some aggressive investors, only that they should be wise with the loan taking as well. If you take a loan that will be difficult for you to pay, that's certainly not good enough, you have to take a reasonable loan that could be paid as soon as possible. But the issue is that, as you are paying the loan, what if the investment fails? That will be the worst part, you will be servicing a loan and you will have lost the investment. This can only be compared to building a property and bulldozed it. This can be very painful and has happened to me more than twice.