Actually that's a badly titled article. At best "Rationality is systematized winning" applies to instrumental, not epistemic, rationality. And even for that you can't make rationality into systematized winning by defining it so. Either that's a tautology (whatever systematized winning is, we define that as "rationality") or it's an empirical question. I.e. does rationality lead to winning? Looking around the world at "winners", that seems like a very open question.

And now that I think about it, it's also an empirical question whether there even is a system for winning. I suspect there is--that is, I suspect that there are certain instrumental practices one can adopt that are generically useful for achieving a broad variety of life goals--but this too is an empirical question we should not simply assume the answer to.