Well, you've switched contexts from sports to studio photography, where use of a tethered laptop or computer is quite normal. The original context was sports and action photography, where the OVF and a dedicated AF unit still rules as king.
No, both contexts are equavlly valid. For action photography you drop the need for predictions regarding the shutter lag. At the same time the AF gets more complete tracking data and the capability to take the guesswork out of focus priority. Add the option of using zebras to highlight information thats hard to follow due to small viewfinder size or just simple motion blur introduced by the human visual system. Thats what actually has an effect on the resulting picture, thats (among)what has killed the OVF in cinematography.
I would take my tethered Surface Pro any day over an EVF, though. There was a thread a while back where I computed the necessary pixel densities to make an EVF screen be high enough resolution for the average 20/20 viewer at a 25mm eye relief such that pixels were invisible.
First: You assume there are no optics involved. Not to think about the structure of the ground glass that can get annoying.
Second, and more important: Its not neccessary to surpass on OVF in that regards, its only a matter of benefits exeeding costs. Is the kind of additional information a type of VF delivers actually helping or just icing on the cake? Contemporary ground glass is quite transparent, combine that with the high magnifications digital brought and a simple high pass overlay wins in the utility department. Tradition doesn't help with taking sellable pictures or keeping production times short.
The day will never come when an EVF (or, for that matter, a tethered laptop screen) becomes superior to an optical view finder for action photography. There is no substitute for a truly real-time, high resolution, bright, optical prism based viewfinder. For action.
Well, those who actually had the choice went with EVFs. Guess that die was cast...so "will not come" is quite accurate.
That guy charging towards your camera position: is the focus point on his eyes or rather on the shoulders? Motion blur and panning are also factors. Edge detection tells me what will be in focus & sharp on the final print, the OVF shows a blend of various motions.
Not really sure what you mean about switchable glass. Sounds like you are talking about the piezoelectric effect, however I am not really sure how that is much different than what Canon already has with their transmissive LCD that overlays their current viewfinders.
The idea is akin to LCDs, but instead of transparent/black it switches between transparent/mirror - integrate it into a beam splitter and you can blend OVF and EVF at will.