Don’t forget SIM swapping attacks which there are services, banks and crypto exchanges still accepting phone numbers as a 2FA method, which is ridiculous.
$3.8B in fraud from crypto out of the over 2 trillion worth of crypto transaction volume is nothing compared to the Zelle and FinCEN fraud with the trillions of illicit transactions allowed by the banks.
> Coins could be made to require two different keys to perform operations.
That's a function of the wallet, we call it multisig.
> Social engineering attacks getting people to divulge their private single keys are a huge method of crypto theft.
Correct and 2FA would do nothing to stop that. The same problem exists with Zelle in traditional finance. To the point that banks are no longer accepting Zelle.