As a reason for the ban, the official cited the example of the FTX exchange collapse, adding that this is only one huge part of the overall problem. According to Brown, cryptocurrencies are dangerous and pose a threat to national security.
FTX was the result of one manbaby and his schoolyard classmates running a $32 billion dollar exchange and getting ran all the way down with it when a bear market kicked in (they did not exist during the major 2018 bear market). That has nothing to do with any other reason that could be tangibly ascribed to "why crypto is bad".