Are the central banks trying to sell you stock at inflated prices?
Astonishingly, yes they are.
(The Economist) central banks start testing negative interest rates
The theory is that having stable and fully capitalized banks is bad. If the bank has lots of cash on deposit, called a
liquidity ratio, that means it's easy to service the withdrawal requests they have. Since commercial bank stability is bad, central banks set the deposit rate negative to discourage deposits and encourage withdrawal. The goal is to get millions of people to withdraw all of their cash at the same time, known as a bank run, and pile all of it into the stock market.
So yes - central banks are trying to sell you overpriced stocks.
I know what your next question is. "They don't want people to buy stocks. They just want bank runs and have people sit on cash!"
Nope. Bankers around the world are calling for outright bans on cash. If you can't store your wealth in the bank, you can't store it as cash under a mattress, and precious metals are mostly a relic of the past, the only things left are the stock market, the bond market, and the real estate market. It's not a mystery why the dividend yield on SPY is less than 3%. It's not because the economy is shit; the economy has been fairly flat for the past half decade. The dividend yield is absurdly low because the stock prices are absurdly high.
The theory of herding sheep into the stock market before welding the doors shut and setting the building on fire is known as the
wealth effect. Bernanke and Yellen have mentioned it many times. It's not a mystery or a conspiracy theory. It's official central bank policy - force people into overpriced stocks because there's no other place to store wealth.