It's not clear that the number of people holding Bitcoin gains, multiplied by the wealth effect, is creating any significant impact on the global economy. Similarly, even if everyone who used credit cards to buy Bitcoin went bankrupt, that still wouldn't be that big a deal for the economy.

Right now Bitcoin lacks the kind of leverage and interconnection with other asset classes that made the real estate crash have a big impact. In that situation, for example, you had banks running 30:1 leverage on some assets, which mean that a 4% decline resulted in a total loss of equity.

> any significant impact on the global economy

I agree. I do not believe the cryptocurrency crash will foment a global economic crisis. I do believe it will create temporary hardships for many Americans, hardships which will in some form flow onto state and federal balance sheets.

When you say "many", how many do you think, and what are you basing that number on? I'm not sure the total wealth from bitcoin to Americans is material to the national economy, much less the potential negative change in that wealth.

The stats I've seen indicate that essentially nobody owns bitcoin when you compare it to other commonly forms of wealth, like homes or traditional equities.

I think one estimate was that less than 500K people - worldwide - own more than one bitcoin, approximately worth $10K. Compare that to the US housing market, where there's 100M-odd homeowners with an average value of ~$220K. Let's say there's 200K bitcoin holders in the US with a bitcoin each, so that's ~2 billion dollars in value vs say 22 trillion in home assets, very rough calc. (And yes, some of those have a lot more than one bitcoin, but some houses are worth more than $220K, and the wealth effect tends to happen breadthwise, primarily.)