Nikon is not really threatening any Canon camera, and Canon is not threatening Nikon.
Each have their proponents, but buyers of that level of camera are most often guided by the price. They go down to Best Buy, and checkout the price of a camera / lens kit and, if it looks professional to them, they buy it. Then, it sits in a closet because the images all look out of focus due to the shallow depth of field, and the controls are too complicated.
Of course, most of those who post here know what they are doing, but they are also a tiny minority.
I've bought many (un)used cameras locally from the closets of buyers who went back to point and shoot cameras because they like everything to be in focus, and they like the ease of use.
My advice to someone wanting a DSLR is to first help them to determine if they really understand what they are getting into. I gave my daughter one of my Canon DSLR's and lenses, I think it is gathering dust as well, since she prefers the old Nikon CP-990 I gave her many years back. She mostly takes photos of projects she has made to list on Etsy or Ebay, and the CP-990 is fantastic for that.
Oh please. No need to be so elitist. Give people more credit. Most people aren't that dumb. Yeah there are many who just use auto on their dslr, but many consumers actually want to learn and that's the reason why they buy the camera in the first place. And these days, people know what specs are and can tell which one is better. If they can't, most people have friends who do know to ask for advice. I mean, people get started somehow right? I started using a DSLR without a clue what any of the settings were but I learned.
Not elitist at all. He right mostly in my opinion. At the same time there are people like you as well. And am sure their numbers will increase!