OK, I'm seeing this question too late, and my answer will probably live a quiet life at the bottom here.
IMHO, this is a variation of something that we have kind of discussed before. What throws us off course here is that "general business" is brought up, so it looks like a distinction done on startup versus general business. IMHO that isn't really the thing to focus on.
The critical part is a distinction between topics which are:
- uniquely related to startups -- business plans, VC financing, product/market fit for example
- topics which concern a common technology or business process which just happens to be used by a startup.
The problem is that if you consider anything a startup happens to make use of on-topic, then in extremity everything is on-topic for this site. How to write HTML (for your startup website), which car to buy (for your first company car) and so forth. And thus the site will become unfocused and meaningless, a kind of discuss-everything-free-for-all like Slashdot or (shudder) Yahoo! Answers.
The above distinction is rarely a clear-cut one or the other decision, it's a judgement call.
I can remember how I first thought of this, but not find the conversation from back then (I think it was before we got a separate Meta site). The question was which hotel he should choose. My comment was that this was off-topic, he should go to Hotels.com or similar. He replied that he needed the hotel because he was in town to pitch investors; and so the question was clearly startup related. IMHO this is a good illustration of the slippery slope this line of thinking can lead to, and that some moderation is required.