This article is more about how you manage risk and learning what your personal risk tolerance is. If you take more or less risk than you "should", then all else equal, you'll wind up with less money.
Besides, these are not "just" math PhDs, but math PhDs backed by some of the largest private equity trading firms in the world, armed with multiple datacenters of 5000 blades each, running machine learning algos and playing "what if" scenarios 24 hours a day, to build rulesets and aligned structured positions so they can scrape news feeds and react in milliseconds.
Anyone who thinks they can sit at home and day-trade with these sharks without being fleeced is a fool. But then, anyone who is a fundamentals trader and is still in this outrageously irrational market is also a fool.
One of the first things I learned as a trader: "The market can remain irrational longer than you can remain solvent."
Now everything financial has been analyzed to death and nobody can make money with technical analysis.