Public markets are fairly efficient, although not perfectly so. The hedge funds that consistently outperform aren't using anything so simplistic as TA on a single ticker. Instead they employ an army of experts armed with enormous computing resources to identify correlations with data outside those markets that no one else has noticed (arbitrage opportunities). They also do proprietary research by commissioning researchers to go out and gather real world data that no one else has, so they are working with an information asymmetry.

Of course, there are also persistent rumors of insider trading. Maybe just sour grapes from inferior traders, but who knows?