I'd say if you're a boomer with £1m in your pension and have just discovered Bitcoin, you can rather safely borrow £40k against it to buy a whole coin. And if your £1m pension suffers a 96% drawdown to wipe you out, you have a bigger risk-management problem, whether you're borrowing or not.

The point is, there is more nuance to leverage that just saying it's dangerous.

Another example: I own a house with a mortgage. My LTV is 30%, which is fairly low. The valuation of my house would have to drop by two thirds to liquidate it. That's very unlikely. If things get that bad, millions of people will get in trouble way before me, and the government will step in and "do something."