When I just want to go to sleep on a normal night, I need it to be dark in order to feel rested and refreshed when I wake up. I've often noted on these boards that I'm one of those people that heads upstairs to sleep when I'm like 45 seconds from being out for the count, and how foolish it is to imagine I'll hear much of an audiobook I sometimes still launch with a 45-minute timer!
However, even supposedly unobtrusive things like nightlights in hallways or bathrooms will sometimes wake me in the night or cause me not to drift off to sleep immediately. I don't use little lights like that in my own house unless I have guests. And I draw a curtain in the hallway upstairs against moonlight.. even now that I don't have cats whom that light made totally nuts.
Oddly, noise doesn't particularly bother me. Those audiobooks definitely don't keep me awake. I do wake up when the village fire hall siren here goes off in the middle of the night, but only because that thing is meant to practically wake the dead in a five-mile radius. I never consciously heard sirens racing past my apartment when I lived in Manhattan, although I remember once sitting straight up in bed because some part of my brain interpreted the winding down of a fire truck siren very close to my building in the wee hours once as very much a potential danger sign! It was a car's battery fire.
In New York I did draw heavy drapes in my apartment bedroom at night, after the city installed the kind of street lights I call riot lights, the kind so bright that they made the poor sparrows nesting in the trees on side streets think the sun never did set. I don't know what it does to birds to have to live like that. Poor things, they had no drapes to draw. That level of lighting at night made me crazy until I did buy the draperies.
Until my mother developed dementia (and, in the early stages in the grip of dementia she used to wander at night, and worse, had a history of bad falls, a few of which hospitalised her, and one of which - when she hit her head against a radiator when falling off a chair - required several stitches), we always had all of the lights off at night.
However, once she started to roam, - and needed light - but while she was still knew enough to be able to find and use the upstairs restroom at night, - when not demented - we started leaving the upstairs landing light on at all times.
This continued after the carer cam not live with us, as she frequently needed to be able to head into my mother at night, and fumbling for light was such a silly thing to have to do.
So, for a period of around eight years, we have had the upstairs light on at all times, and I have more or less gotten used to it.
These days, although I am now by myself in the house, I leave it on most of the time, and occasionally turn it off.
Ah now we're getting down to it. Snoring! Yah that's a noise I don't deal with very well.
A heartfelt and profound amen to that.
Even though I am opposed to the death penalty, like the wimpy European I am, the violence of my fantasies when I am anywhere near a prodigious snorer, would give the lie to that.
Now imagine sitting on a 4 hour plus flight with a 250 lbs man next to you in economy class snoring and breathing on you with each snore. Asides from that the air that came out of him was stronger then the air from the air vents from above the seats 😝

I had my face mask on but was really hoping he would put one on too. The amount of air and noise coming out of him was like out of the blowers the gardeners use. I was literally sitting next to a beast for the second part of my flight. He slept well. Cared nothing about noise, where he was seated, how he was seated or anything else. He literally slept like a beast.
You have my deepest and most heartfelt commiserations.
I can understand how people who do regularly have problems getting to sleep --or getting enough good quality sleep-- would long for the ease with which the rest of the world seems to find sleep within minutes when they need it.
I know it's really hard on new parents... I was thinking about that after reading
@stylinexpat's post immediately above. Talk about sharing a sleeping space with a beast! An infant's cry is meant to be what it is, a five-alarm-fire kind of noise to summon mama and so a means to survival. But the whole household (or a car, bus, airplane, bank or supermarket!) gets to hear that expert demonstration also. I always tell myself to chill out because I'm not going to hear that kid sceaming on a regular basis for months on end...
Oh, yes.
Shrieking infants.
The maternal gene must have inexplicably by-passed me, but I never hear a screaming infant on a plane or a train without harbouring brooding thoughts of homicide.