Sony went into the phone sensor business, and this is where they get their R&D money from. And of course, soon it will be car sensors etc. The cameras are more of a byproduct of their sensor component operation than a driving force, so in a way Canon is faced with competition with a bottomless R&D budget, and in fact we can see how Sony has upped the competition in 3 years.
As you point out, this looks very much like Detroit vs. Japan Inc. with Canon stuck in the role of Detroit.
On the other hand, a lot of tourists in Paris sport huge useless dSLRs which seem a requisite fashion accessory, just like flashy fashion sneakers.
Edmund
I have moved on from Canon EOS to Sony A7 system, for lighter weight, and smaller travelling system, without compromising on quality. I think your last paragraph is way off mark though... Regardless of what the "specialists" and "tech gearheads" prophesize, DSLRs provide some of the best bang-for-the-buck for the "average" photographer that wants to carry more than a smartphone. Heck, for 300-400 Eur, I can go to the shop and buy a DSLR plus two zoom kit...
And they are anything but useless... fashion accessories, really?
As for the AF on the new Sony using EF lenses, well, let's wait for the performance when tracking moving targets (not someone seating at a table...), or when light levels go low...