I think we're actually regressing back to the 70s, in terms of photography. Back then, "enthusiasts" might have a Pentax and threes lenses (35, 50, 135), while consumers mostly shot Instamatics and maybe Polaroids. Only pros, or aspiring pros, had the heavy stuff -- I remember when I got out of the Army in 1968, yearning for a Nikon and just a modest set of lenses. But if you weren't a pro, you could hardly justify the purchase.
Now, the Instamatic slot is being taken by cell phones. Enthusiasts, who until recently were buying a whole range of cameras, I think are beginning to see that for their purposes the ~$1,000 mirrorless with a few zooms is all they really need. Very soon, only the pros or aspiring pros (and some status-conscious enthusiasts) will be looking at the big guns. In fact, I think a good chunk of the enthusiasts would be pretty happy with a non-interchangable Nex-form or m4/3-form mirrorless camera with something like the current f 2.8 Panny 12-35 or Olympus 12-40 permanently mounted on it. They are fine lenses, with good group shots at one end, good portraits at the other. If somebody does that -- mounts a really good fast zoom on a quality body, I think it might really cut a chunk out of the enthusiast sales.
But overall, this new alignment (going back to the 70s) would mean that the camera companies would shrink rather severely. It's possible that that's the natural result of the aging of the baby boomers, moving out of the affluent "hobby" years and into less affluent older age.