I've seen this on United previously ex-LHR to western USA and the FA's got very aggressive with a person who was trying to keep the window shade open about 1" to read by.
I know everyone's body clock is all over the place but if the airline wanted to help you sleep it wouldn't install such crap seats so close together (in economy). Basically what's the point in having windows, lets save a few kilos of structure and just do without.