I was always confused as to why Apple didn't provide a styling guide! Of course, it can't be definitive but it would go a long way, especially for beginners.
Should there be an official style? Yes.
Should there be an official formatting tool that enforces this style? Yes.
Should that official formatting tool be configurable? Yes x 1 million (if this is no, forget about the above)
First and foremost, code styling is highly debatable and even if Apple or The Swift Team provided one, we would definitely still be arguing about it.
However, if we had an official guide, a developer could write more readable code from day one. It's really hard to train a developer to write like so. Especially after a while where their thinking settles in. I see a lot of poorly written code by junior developers where they've no idea about the value of properly formatted code.
Having such a formatting tool would be like an always-on tutor providing guidance. Of course, there are such tools but having it integrated into Swift/Xcode would be much better.
And if we have such a formatting guide, I think the Swift team should provide one specifically for the Swift Standard Library and Apple should built on top of that and provide one for their frameworks.
That being said, people will and are free to have their opinions of their own. A seasoned developer/company can have their own take on something specific. Therefore, most certainly, such a formatter must be configurable in every aspect of its.
Moreover, if that code formatter is configurable, people can easily switch other code to their style while reading them. Computers are fast and smart enough to be able to format the code to my liking when I open the file. Therefore I think with such a formatter and its configurable options, people would be happier to read someone else's code.