Brian Armstrong, the CEO and co-founder of the largest cryptocurrency exchange in the U.S., Coinbase (NASDAQ:COIN) , has dropped out of the Bloomberg Billionaires Index, which ranks the world's 500 wealthiest individuals.Armstrong's departure from the list of the world's 500 wealthiest coincides with a steep crypto market decline, as Bitcoin drops below $70,000 for the first time since late 2024. His fortune remains heavily linked to his roughly 14% stake in Coinbase.Per the Bloomberg index, Armstrong’s net ...