The whole concept of running the hamster wheel in the first place is flawed; who are you "falling behind" if not comparing yourself to other people.
The article wants us to "take a fucking step back for a moment, stop beating ourselves up into oblivion, and to let the cogs turn as they will". What I'm saying is don't put yourself in that situation in the first place. Take joy and find meaning in the day-to-day of what you're doing, instead of setting the expectation that you're supposed to be "better than anyone else", at anything, really.
joslin01 said it pretty well in another comment: "It's best to be honest with yourself and come to terms with where you are in life and where you want to be. After that, unless you put action into your belief, you will be sad. Even if you fail, but put action into the belief, you'll be happy and have grown."
So, I implore you, what is something you're actually going to do with this self-help article's new-found insight that you "can't control everything" and need to "just chill"? Will it bring you more happiness knowing that anytime you're running yourself ragged you can "step back" and reassure yourself that you're "just human"?