In 1982 I was working in the phonograph cartridge industry and went to an audio engineering show where I saw an early CD player. It was clear to me that phonograph records were doomed but what was surprising was the speed with which it happened. Technology shifts go even faster now.
I agree with what Havoc315 wrote, except:
2018 we get mirrorless cameras from the big 2. They sell quickly.
2020 is the last new design dSLR and lenses specifically for it.
2022 dSLR has 1% market share.
Technology change is funny... It can be slow at first and then suddenly quickly accelerate. Often due to a shift in pricing or a tweak to the technology. E-books were crawling along until
Amazon Kindle. Then they exploded..... yet their growth seems to have stalled. As if they went from 1% of the market to 50% of the market overnight and then just stuck there.
I remember early days of DVDs... DVD players were expensive, over $500... And there were limited movies available. The stores were giving away 5 free movies when you bought a DVD player. But when the price dropped to the $200 to $300 range, suddenly everyone was buying DVD players and VCRs disappeared overnight.
There are a couple factors that could work in the favor of dSLR holding a decent position:
-- The market is shrinking overall. Thus, there aren't huge masses rushing out to buy new products. This slows down change. In some ways, it's like the DVD ---> Blu-Ray transition. As most people abandoned discs in favor of downloads, there wasn't a rush to Blu-Ray.
-- APS-C dSLRs are still cheaper and more available than mirrorless: That's partially due to the glut of dSLR inventory on the market, it's also due to the maturity of the product. Nikon isn't even doing an aps-c mirrorless yet, they are going straight to full frame. Seems it will be at least 6-12 months before they go aps-c. Thus, entry bargain shoppers may still be drawn to apc-s dSLRs.
-- Conventional wisdom can be hard to shift. This is a dam burst thing -- once mirrorless recognition reaches a certain threshold in the public, it might be a non-issue. But for now, huge numbers of consumers don't understand the difference. They see a dSLR and they think "that's a real camera." And if it doesn't look like a dSLR, they assume it's not as good. I teach introductory photography classes, and I find that mindset all the time. And getting back to the shrinking market, that slows down the change in recognition.
-- Lens investments, though that's similar to VHS and phonograph investments. But people with $5,000 to $20,000 in lenses have a vested interest in continuing their traditional dSLR mounts.
That's why I generally agree with you, but I don't think the transition will be that complete and that fast.
But I do wonder whether we will ever even see a traditional Canon 5D5 or Nikon D860.
2018 will be an interesting year for the introduction of the mirrorless models.
But 2019 will be fascinating to see where Canon/Nikon put their attention, the degree to which they go back to their dSLRs.