There are a bunch of estimates on this, and I would say based on what we've seen lately with FTX that there is likely an even larger amount of fraud in the system than is known. Yes the USD is also used for illicit activity, but thats just cash, and we actively try to stop it.
Agree about FTX, but much of it was unsurprising to those paying attention, and that wasn't merely fraud about Crypto, that was an epic failure on the part of a few of the world's preeminent investors.
>but thats just cash
I'm not sure what you mean by this, can you elaborate? Every estimate I've found is very poor quality data, and I'm happy to pick apart any. It's similar to the energy use estimates which are equally poor and often miss vital distinctions.
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