The Hollywood-inspired folk concept of Wall Street is that they trade stocks. That’s what everybody in those big buildings in Manhattan does all day. They yell buy/sell orders into red phones and drink Scotch.
Except they don’t. Wall Street firms like Goldman Sachs make money by providing services such as mergers and acquisitions, IPOs, market making, etc. That is, they make money by selling shovels in a gold rush, not by speculating on where gold will be found. Other firms are in the business of buying and selling illiquid assets such as private companies and commercial real estate (with illiquid assets, there is far lower price efficiency, and thus it is possible to generate excess returns). Still others are in the business of managing people’s money for them—an industry which is mostly about managing volatility, not about generating excess returns (a pension fund usually cannot afford to have its portfolio go down by 50%, even if it’s temporary, so they’re not going to put it all in the S&P 500).
Proprietary trading (where firms use their own money to buy and sell public securities) has been in decline for decades at the big banks, precisely because they don’t have a scrying crystal, and they know it. Public stock trading on Wall Street is mostly the domain of companies in niches like high-frequency trading (such as Jane Street). HFT firms gain an edge through arbitraging different prices faster than anyone else (for example, sell Exxon in New York a few microseconds after oil futures drop in Chicago). In other words, the only people on Wall Street who do what Hollywood-Wall-Street does are the few who do have a scrying crystal.
WSB is not “exposing” anything except the fact that most people (understandably) have no idea what the financial industry does.