If investing in SPY beats most investment strategies long term, what’s the point of quant traders? Short term findings?Aren’t most destined to fail, and at least some who don’t might have gotten lucky? What are main strategies? Still revolving around SPY?

Just curious. Any input would be appreciated.

Edit: It is clear I have a lot to learn. Don't know much. I'm a stats grad student, haven't really touched finance modeling. Thinking of getting into some of this stuff during PhD, but not main focus. Prof said become a top tier statistician and you'll learn finance stuff on the job. Anyone have any good beginner books? I'm taking stochastic models class this semester and we're covering stuff like Black-Scholes and other fundamentals.