It's more about how much you care that things like that are logically supported by and can be derived from the answers to questions like "what is physical reality?" For ancient Stoics—the ones who developed the philosophy—this was more important than for most people reading it today to learn how to be happier or whatever. So a modern reader might say "it's weird that this writer emphasizes determinism in their description of Stoicism" while an ancient Stoic might think it's weird that (basically) everyone interested in Stoicism today minimizes or ignores their physics.

[EDIT] not to say their physics & metaphysics were constant over time—Stoicism's period of serious activity spanned centuries, after all—and that much of their "lower level" philosophy wasn't very likely produced by working backward from their conclusions, which is common in philosophies that attempt to prove or support their ethical beliefs in such manner (see also: "natural law" or "natural rights")

[EDIT EDIT] and I'm not claiming that original approach is the superior one. It's just why there might be a difference in opinion over what's essential about Stoicism. The utility of a Stoic mindset may well be pretty unrelated to an underlying approach to the problem of evil, a statement about the nature of the divine, claims about what reality actually is, and so on.