Why be so concerned about the 787? My experience these days is that passengers have no control over any blind, manual or electronic. The crew on day flights go around telling people to have them down and in some cases get the senior purser to tell off those recalcitrant PAYING passengers to do as they are told.
I can supply a list of long haul airlines operating this policy in my substantial experience.
Night flights I understand the need for the policy. Day flights I don't. I have seen on here, and heard people say it is because there are passengers who joined the flight and are in another time zone and therefore need to sleep. It is in my view another degradation of what was once a wonderful experience. For example, flying over Greenland, flying over northern east Russia, flying over Siberia, flying over the Oman, flying over north west Australia, seeing the Himalayas when crossing India, crossing Baltistan, seeing Afghanistan in both the summer and the winter, flying over Mont Blanc. All stunning views on a clear day.