It's so bizarre that camera manufacturers never figured out that the camera should be treated primarily as a smartphone peripheral. When I take a picture on the compact camera it should automatically sync to the smart phone camera roll with geotagging. All of the camera's settings and shutter should be controllable through a smartphone app. This lack of integration was a real failure of vision by camera manufacturers.
In case of DSLRs, and their mirrorless offspring, the purpose and the target audience's need is to capture light as good as possible, using a combination of precision electronics, optics and mechanics, to be edited later. They threw in some basic editing functionalities, various image formats and what not, but those are not mission critical.
Smartphones are lacking the optics, sensors and some other things a real camera has. As a result, they are still a far cry from replacing mid-level and up cameras. Smartphones, as the article points out, are perfectly sufficient for the compact and point-and-shoot market, and as a result killed it / took it over.
And heck, the ergonomics of Nikon blow any smartphone / app way of setting up a camera out of the water ever since before Nikon got serious about DSLRs.
The technology lifecycles haven't lined up. 10-15 years ago there were phenomenal DSLRs coming out, and honestly there weren't any good enough smartphones worth connecting them to. The iPhone App Store was in its infancy (it's only 14 years old); there weren't / still aren't any good, widespread standards for fast, personal-area-network data transfers of photos. Smartphones didn't have a lot of memory either: the iPhone 4 baseline model in 2010 ran with 4 GB, and the top of the line was 32 GB, with no slots for memory swapping - not something you can sync a lot of photos to at all.
I don't think, 10 years ago, camera manufacturers could've adopted a meaningful integration strategy. They could perhaps have entered the fray as Android phone makers and try to solve it, but it would've been a bigger jump than just integrating.
My 2016 Olympus does this, too. The controls are surprisingly good (you get cable-less bulb mode), and you can even get the live image on the phone while shooting. There is some lag, though, so it won't work for moving subjects.
Sounds like you're complaining about a lack of vision because they couldn't mix technologies from different years, or have the budget to make a phone as well as a camera...
But it does seem to be a clever idea, I'm imagining a phone that has surface contacts on its back, and a Go-Pro-sized camera module that you can attach to the phone (with precise magnets, so the surface contacts on both devices would connect both devices electronically as well) and be recognized as a peripheral for the phone.
But I guess if already have a pro camera, you don't want to need to slap your phone on it to get it to work.
That exists, the Sony QX100. Nobody bought it because it’s not quite as good as a real camera and it’s something you have to remember to bring with you.
The whole lag and connection issue shown in the video is probably why grandparent comment's idea hasn't taken off. Since no phones have surface contacts, maybe if the lens had a USB-C connection it'd be a lot better (but no closed-garden iPhone support, obviously).
