I think Sony introduced the E mount as they thought it would attract more professionals from Canikon, they did claim that they would capture the lead within a few years of taking over Minolta. They failed to attract enough pros with the A mount, possibly due to the EVF. The E mount has had considerable success, but not quite as good as Sony had expected. So now Sony are trying a new strategy, bring back the A mount complete with all the new innovations from the E mount, keep the E mount and in that way get enough followers to justify staying in the business.
I wouldn't hold my breath for the next couple of years, if you know what I mean. There is no doubt that Sony is the most innovative of the companies making cameras, but Pro. photographers are the most stubborn and resistant to change people on the planet. They have had optical view finders from Canon and Nikon for decades and do not think they like the Electronic view finders, even though they are demonstratively superior. Perhaps Sony should stop selling sensors to Nikon and the others and Nikon would suddenly find that EVF is the way to go. Canon and the others may then follow suit or perish. Alternately Sony may just call it quits.