Earlier quoted context omitted.
> As a retail investor (i.e. not extremely rich), you can't gain any advantage over the market that overcomes your transaction costs. Sure you can. You develop a system, learn how to find information, and make good predictions of future human behavior. You should learn the ins and outs of the product you're trading.
Very few active fund managers can consistently beat their indexes. Why do you believe you would be better over a long period of time? Vanguard Study of Actively Managed Funds vs Index Performance: https://personal.vanguard.com/pdf/ISGIDX.pdf
This is why hedge funds underperform indexes in bull markets but beat them in turbulent times.