This difference between content and style is a continuum. For example, the main claim and argument of an essay is more content-like than are diversions and comments, which are less likely to be remembered or understood by readers. Subtext is even more style-like, as fewer readers can notice or repeat it. Subtle choice of vocabulary and sentence structure can be even more style-like.
i may nave made my living with my pen, but I can’t say I’ve thought much about style. Just get the facts straight. Let style take care of itself.