There's two different debates going on here simultaneously.
First - whether the cabin should be made dark during daytime flights and/or whether the 787 dimming is sufficient vs manual shades for sleeping in daylight.
Second - with the crew having made the decision to make the cabin dark, whether individual pax should be allowed to overrule this to suit their own preferences, and therefore lighting up the entire cabin zone.
I can see many valid arguments for & against for the first debate, but I really don't understand how someone could argue for the second.
