You can never trust headlines like this, for several reasons:

1. No one can accurately predict the future of the stock market
2. If someone could predict it, they wouldn't go around telling people

The likely scenario is this:

1. The big banks conspire to sell shares and drop prices
2. They hope retail investors will follow suit due to headlines like this AND a short term drop in prices
3. The big banks buy back in near the bottom, and ride prices back up into tendie town

Best strategy is to buy and hold index funds.