I don't normally see the "currently" verbiage anymore; I think it appeared often in the past because we were one of the first Stack Exchanges to go into beta and for a long time we didn't have moderators or any real consensus about what the scope was supposed to be. (And even when we did get moderators, most of us pro-tems were initially gun-shy because we were pro-tem, not elected).
So, really, you shouldn't see the word "currently", at least not in a new or recent context. If something is off topic, it's off topic. There aren't any deliberate plans to change the scope any time soon.
You asked what determines the scope. Our scope, and the scope of most SE sites, is a product of several different factors:
- The initial Area 51 definition;
- Various debates, shakedowns, and filibusters from the beta period;
- Precedent-setting questions that crystallized previously-ambiguous subject areas;
- Ongoing flags, close/reopen votes, and meta discussions (to a lesser extent).
The scope is by no means arbitrary - it's specifically chosen with the stated aim of attracting and retaining professionals or at least serious enthusiasts. And while we don't need to be reminded that we don't always succeed in that goal, we still have to try our best, and that means (a) having questions that are actually interesting to those with knowledge and experience, and (b) not allowing those questions to be buried by other low-quality or off-topic questions.
At the same time, the non-mention of a particular subject doesn't mean anything, positive or negative. If it's not mentioned in the FAQ, then maybe it's so blatantly off-topic that nobody thought it was worth mentioning, or maybe it's a perfect topic for the site but just one that nobody thought to ask yet.
So, is the scope up to discussion? Yes, but the bar for expanding it is a very high one to meet. There has to be clear evidence or at least a very convincing argument that the subject is:
- Of interest to culinary professionals or enthusiasts, and within their domain of expertise;
- Uniquely of interest to culinary professionals or enthusiasts (i.e. it is not a topic of general interest that could be discussed anywhere);
- Objective to at least some degree, i.e. the answers should be verifiable either with facts and references or with direct testing and a well-defined end result.
Everything that's been declared explicitly off-topic is seriously deficient in at least one of the above areas:
Recipe swaps are too open-ended, never have a clearly-defined end result and can be answered by virtually anyone regardless of culinary experience;
Health and nutrition topics are the domain of dietitians; chefs will have some knowledge of this but only in an applied sense, i.e. creating menus or customizing dishes to meet specific nutritional requirements.
Career advice questions have proven to be a disaster on every site they've been tested on; mostly they revolve around the same tired old topics ("Should I go to work or stay in school?" / "I'm in over my head, what do I do!?" / "Don't you just hate co-workers?") and it goes without saying that answers are invariably impossible to rate or verify by any objective criteria.
Brewing/winemaking is a great topic for Q&A, it's just not normally in the domain of a chef. Besides, the topic already has another home on Stack Exchange.
At this point, I think it's quite unlikely that you'll be able to convince an influential majority of the community that any of those topics are worth having here, but that's not to say we're unwilling to listen to a reasoned argument. For example, culinary-uses questions were sort of a compromise on the subject of recipe requests. Additionally, while the typical shopping question (recommendation) is off-topic everywhere on the network, certain formations of the question are allowed. So we do listen, and react, and collaborate, but we do so guardedly, with a generous helping of skepticism.
If there's a more specific aspect of the scope you wish to discuss, feel free to do so directly; no need to beat around the bush. It's extremely rare for anyone to get punished or mocked for presenting an issue tactfully; the worst that can happen is a status-declined.