Grit only gets you so far, and higher-than-normal levels of grit can be a real problem. Grit will counteract squeakiness (as in "the squeaky wheel gets the grease"), which is not what you want when the sources of most of the problems you're encountering by that point are external, rather than the kind of internal struggles that most people deal with—the kinds of people who are the target audience for gurus like Ryan Holiday and his takes on e.g. "winning the war with yourself". Those people definitely benefit from more grit. Some people might need less of it. (That is not to say smaller doses of the supplement, but rather to lower the latent levels of what's already on their system.)