@annk
So just to be succinct, forget iPhones completely, why do we have different MacBook sub forums?
I'm re-reading what you just typed several times and it doesn't feel like it it answers that question very clearly, or perhaps I'm just not understanding.
Or if you do want to relate it to iPhones, what is it about the different MacBooks and the differences between each line that necessitates different forums for each that does not apply to the iPhones?
Thanks again
I appreciate all the attention you're paying this
We always have discussions about forum structure when a new product is launched, so I've put this response together from a combination of points raised and discussed by several moderators and administrators.
Specific to your question:
With iOS most people update to the latest version (if their device permits it), while with macOS many people stay on older versions. And that may be because people tend to replace phones more frequently than they replace desktops and laptops, so they get stuck on older macOS versions. This means less stratification of models and features in the iPhone section than in the macOS sections, where we still see people on 2008 models with Lion 10.7.x asking questions.
When moderators post in order to help people with laptop problems and they see questions such as "can I do xxx"... or "why is xxx happening", their answers will often be very different depending on the macOS version involved. That's why it helps to have the separate sub-forums. Otherwise they first need to ask which macOS version they're on.
For iPhones their answers to those same questions will almost always be the same regardless of iPhone version. Unless someone has a really old iPhone, it is usually safe to assume they are on iOS10 or iOS11.
General aspects of forum structure:
There are tradeoffs between having distinct forums for each product variation and leaving them combined. Distinct forums let people focus on discussions about one model or version with fewer distractions, but make it harder to find discussions about the product in general. Not all discussions are about a specific product model, but some obviously are. The latter tend to be most frequent when the product is new.
We have to limit the number of forums because the more sections we have, the more people have to scroll past them to get to other forums, and the more trouble it is to figure out where to start a new thread. This is more of a problem for new forum members than for long-time forum members who know their way around and see the slow evolution.
We study these tradeoffs for each new product.