Back this morning from our Mediterranean cruise. Barcelona was our port of departure and return. I have not been to Europe since my honeymooon, so I forgot how uncomfortable that trans-Atlantic flight can be. It was about 6-7 hours going and 8-9 hours flight time on the return (although I overheard one flight attendant on our flight getting off the plane saying that it was a 10-hour flight, so she and I must do math differently

)
Thanks to airline miles, we were able to go business class for US-BCN-US legs of the trip. Otherwise, we surely did not have the $3K+ per ticket to swing that luxury. But yes, I would say that it's a hugely nice "essential" if it can happen one way or another for anyone.
I know that for health reasons, it is not optimal to drink alcohol or soda on the flight, but the one glass of wine I had with dinner helped me fall right to sleep on the flight over. I also had sleeping pills and melatonin with me (would have taken one or the other if needed, but it was not).
My iPhone music helped me relax on the flight back. That and reading magazines made me drowsy.
Facial wipes helped me feel more alert and clean up a bit before we landed, but then I needed Aquaphor for my hands and a bit on my face because my skin was visibly dry and flaking. My hands almost hurt from being so dry.