I wouldn't be surprised if the number of actual dollars was less than $100 million.
If I buy 50 RandoCoins for $1 today, tomorrow it shows that it's now valued at $2, and then the next day RandoCoin is hacked and all the coins are stolen, I didn't really lose $100, I only lost $50.
So he's wondering if the value of loss is being expressed as the money used the purchase the coins or the perceived value of the coins.
BTC for instance has a 24hr TV of $37B, making it one of the most exchanged assets in the world.
To give a hypothetical example: Alameda, as a customer, deposits magic beans with a mark to market value of a billion dollars. Then Alameda trades the magic beans for a billion dollars of BTC-perp (FTX paper bitcoin), with FTX acting as the counterparty (which I believe they typically were for trades of the perpetuals). Now FTX's balance sheet reflects $1 billion in Bitcoin liability (plus being long $1 billion worth of magic beans)-- but in this example no bitcoin had been deposited at all-- just magic beans.
When sizing up the losses, all liability ultimately resulting from magic beans ought to be backed out. This is exit complicated because some of the magic-bean derived paper assets have presumably been withdrawn using customer deposits, and those funds are actually lost even if the depositors that brought them in never traded (and simply deposited in FTX because of the ponzi-scheme grade yields they were paying depositors).