1) Jane Street isn't that successful.
2) RenTech spends billions every year on compute, data and hiring the smartest people in the world.
The average person could never compete with RenTech.
The average person could never compete with RenTech.
Grandparent claimed that active investing is not good for _anybody_. A single example (like RenTech) is sufficient to disprove that claim. If you want to move the goalposts to "the average person", then it'll be an entirely different discussion.
Their historical record is very good.