I've recently flown Sydney- Dubai, a 14 hour flight. Keep in mind a LOT of people use sleeping drugs for this flight. Because it's miserable.
The meals were served an hour after take off, two hours before landing and a small meal in the middle.
After the first meal the lights were dimmed to pitch black and everyone reclines their seats.
For the next meal, about 4 hours later, the lights are only turned up slightly, a lot- the majority, even- of people stay sleeping and reclined. After about 45 mins lights completely dimmed again, everyone reclines.
For the last meal, the lights were turned up properly, a lot of people start to wake up and put their seats back up. After, plenty put them down again until told they have to put them up for landing about 15 mins before landing.
So in a 14 hour flight, the majority of the plane has their seat reclined for about 12-13 hours.
I had three small children with me and slept for about 30 minutes of the flight, we were up and down the whole time. Did it annoy me that the people in front reclined the whole time? No, what a joke, why should they have a more uncomfortable flight than long haul economy already is, for the very minor inconvenience that their recline already caused me?