You should care: mirrorless is the future of Canon's camera business; more to the point, it's the future profit of Canon's camera business.
It's amazing how people keep saying things like this even though the mirrorless market has failed to materialize in the U.S. and Europe, and is still a side market in Japan.
And this is coming from someone who loves his EOS M, wants to see more EOS M bodies and lenses, and thinks mirrorless in general is underrated by the public.
The DSLR isn't going any where, and Canon's profits will continue to come from brisk Rebel sales.
I'm not saying that current tech is good enough to replace the reflex system right now, or even next year. However, a modern SLR with live view is almost exactly the same as a MILC plus a mirror plus an OVF. As AF, EVF and battery issues are addressed, what manufacturer would choose to add costly and redundant mechanical parts to its products? In other words, the mirror assembly has been a very effective kluge for several decades, but it's time to move on. The only question is how long it will take for each of the different lines.
If Canon develops live view AF that rivals their PD AF, you can bet they'll get that tech into the next 1-series body as fast as they can: what sports shooter would not want the ability shoot at 30fps with continuous AF? They'll have Nikon shooters switching in droves. (yes, I know the current sustained fps bottleneck is memory throughput, but mirror movement is also an impediment)
As for EVF lag, the eye itself has a 100ms lag. There's at least one MFT EVF today that has only 30ms lag. If you cut that to 15ms you'd probably not notice any lag.
We can't predict exactly when the tech will reach the level needed to fully replace reflex, but the days of the mirror are numbered.