Interesting thought about the implications of "crypto winter"!
Part of me wants to say this is separate from USD money supply and monetary velocity, except for the psychological wealth effects. If cryptocoins lose value in terms of USD, that's no different than any other asset losing value in terms of USD. It shouldn't affect people's willingness to borrow, spend, or save dollars. And if a hacker or fraudster steals crypto or cash from a person, that only changes who owns the crypto and cash, not the amount in circulation or the speed at which it circulates.
My original understanding was that FTX took dollar deposits, allowed people to buy cryptocoins, sold their clients' coins, leaving them with IOU's (so far very similar to what your stock brokerage does to a limited extent), and used the proceeds to run pump-and-dumps on smaller coins like Serum or stocks like Robinhood, running 10:1 leverage. If that were the case, they'd only be unable to handle a bank run if the arbitrage between their coin liabilities and their coin/stock assets went the wrong way, and maybe Robinhood stock would crash because FTX would have to sell their entire stake all at once. Even in that case, it would be a matter of the brokerage being unable to supply the assets their customers demanded to sell, and the supply of dollars would merely be redistributed from FTX account holders to FTX's counterparties.
However, according to the Financial Times, FTX also had dollar-denominated liabilities, though it's not clear if those dollar liabilities emerged when clients tried to sell their crypto and get out of the platform. I'm not sure anyone but FTX or Binance employees understand at this point. FTX apparently did not have the cryptocoins people were asking for during the bank run because they were essentially shorting their customers' coins while going long more illiquid things. They only held IOUs for their depositors' assets, and these IOUs represent a liability. So when a client clicked sell on the X number of bitcoin showing on their screen, in the background there were not X bitcoins in FTX's possession that could be sold!
https://www.ft.com/content/f05fe9f8-ca0a-48d5-8ef2-7a4d813af558Again, I think all this damage stays confined to the crypto universe until we find a link to the dollar economy, or the contagion spreads to Binance and other crypto exchanges. So far, the episode seems to have sparked a run on U.S. treasuries as people flee to safety. Rates have fallen dramatically in a week. Some banks and hedge funds loaned FTX money and will likely experience losses, but this only affects inflation or the real economy to the extent they're less able to make loans. The redistribution of dollars from FTX account holders to FTX counterparties does not change the number of dollars in circulation, and probably won't do much to change their velocity unless the new owners of that money have a different propensity to spend.
Now, if a major dollar-based bank reveals crippling losses from crypto, or tens of thousands of crypto/tech workers lose their jobs, or whiplash in the futures markets destroy a hedge fund, then all bets are off.
