I don't work for Ryanair but we're always getting asked to turn the temp up or down in all sections of the aircraft - the crew usually ask the flight deck straight away and then all questions from pax cease. Problem solved. Don't see the point in doing nothing about it as you'll only have pax complaining for the whole journey. if I myself find it too hot/cold in the cabin, I'll go and speak to the F/D about it because I'm sure it's bothering pax too.