Yes I do edit 12M images on a ~15M monitor. Its also the weak point in the system, as your average midrange+ DSLR is 25-50M, and its pretty easy to create a printout where the effective resolution of the page/poster is vastly higher.

But that is not really the point, the apple presentation goes on about how the machine can play 3 8k video streams simultaneously, but you have to buy a 3rd party monitor/projector to even be able to view a single stream.