One thing the series really does hit home is that the game is rigged against regular people. You're either inside or outside - sure regular folks can earn returns, but the reason that the rich get richer and no one else makes real ground is that the wealthy don't play by the same rules.
Is the stock market still about providing capital to firms that are creating the means of production and growth? Maybe, but that's now far from the only reason the markets exist. Now they also exist as a means of wealth transfer and literal gambling - often with other people's money.