This represents a significant step forward in camera technology, the culmination of many years research and significant investment in a single package. All innovative ideas seen in one form or another, reaching maturity in a single package. BSI, high sensitivity, Evf, high resolution, high speed data transfer, on sensor af technology, ability to attach all manufacturers lenses with high speed auto focus support etc... Don't under estimate what a significant camera this is.
Canon will not be able to respond to this overnight, not without major investment and R&D, Sony level investment in sensor is very significant. Most image sensor scientists agree Sony is 3-5 years ahead of canon in sensor technology design. This gap will be more and more obvious going forward, consider how short a time sony has achieved this strategy. This camera was no accident, shows considerable forsight and will. If I had canon pre order I would cancel and attach my L series glass to the a7rii instead.
It's not just the camera, it's what it represents.