Admittedly the original intended purpose of the stock market might not have been control but that's certainly a big feature of it now.

Unless you are already ultra wealthy there is little to gain from individuals entering the stock market directly.

It's a vehicle for those with power and/or money to gain more power/money by siphoning it from everyone who isn't them.

Sure, some people make money, in the same way people in a casino make money.

The house, however, always wins.