If you actually don't understand why that citadel statement said that you should read up on how market makers work. Any given snapshot in time for them would have enormous quantities of securities on both sides because they have to hedge all of their activities to remain neutral to any price movements.

>So when exactly will that $60 billion of buy pressure hit the market?

it probably did shortly after the statement, coupled with a likely similarly sized "sell pressure". They're constantly buying and selling things that's how the business model works