Upload & Sell: Off
Well, seeing that quality mirrorless options (by quality I mean arguably or actually equal to cropped sensor) are such a new thing that they don't yet have mind share among those who "know" the DSLRs from Canon and Nikon (and maybe Sony and Pentax) are the "good cameras."
This new kind of camera is barely a year old!
Dan, I don't think this type of quality is the reason, people moving up can get the quality they want/need with a 5+ year old DSLR or an early-generation mirrorless.
I think part of it is that when compared to a smartphone, everything is far larger. And once you start bringing things like zooms into the picture, the size differences start to diminish.