That's not entirely true. The effect you describe depends on loan growth. Money sitting in bank accounts isn't automatically funding anything. There has to be demand for loans and the banks have to be willing to lend, otherwise nothing happens.
In other words, there's a difference between capital being available and capital being put to use. Velocity of money is important.
Also, if I buy Apple stock today, Apple doesn't see a cent of it. Whether or not that money goes on to fund anything at all depends on what the person who sold me the stock does with the money.
Sure, but that in itself does not make the economy grow. It could potentially make the economy grow if the person I buy the stock from uses it to buy other shares in an IPO and that company spends the money to fund actual work. Or if that person just puts the money into consumption.
I'm just saying that boosting some share price does not in itself fund any labor. That's important, because the difficulty of getting the economy growing again after a balance sheet recession like the one we just saw, is to get money moving, not just sitting somwhere with a nominal price tag on it.
In other words, there's a difference between capital being available and capital being put to use. Velocity of money is important.
Also, if I buy Apple stock today, Apple doesn't see a cent of it. Whether or not that money goes on to fund anything at all depends on what the person who sold me the stock does with the money.