In response to the article it might be deliberate "coshing" but OTOH it's worth being aware that on at least one type mentioned the AC system, as installed, will automatically slightly increase cabin temperatures during the early part of the cruise in order to compensate for the reduction passenger activity (it would wash that increase out on the descent). It is possible that not all the temperature increases claimed in the article were demanded by the crew.
Personally I've never been approached by cabin crew to crank system temperatures up to get passengers to sleep, but then again from the flight deck display I will admit to have occasionally seen some zone temperatures set to suspiciously high values by other crew members.
Last edited by wiggy; 22nd Mar 2016 at 08:22.