Teenagers stay up late because they’re waiting on their parents to go to bed before they engage in their teenagery shenanigans.
Yes. My parents both developed insomnia problems as they got older; my mom got prescription medicine to deal with it before my dad, but now my dad does too.
My brother and sister slept soundly when they were young, but they both developed insomnia problems in their 40s and are now also on prescription meds.
I used to sleep soundly too - but now that I’m in my 40s, it’s happening to me too. Not bad enough yet for prescription meds, but I know my day is coming.
More likely you’re the one with sadly limited observations. What the OP is describing is called Advanced Sleep Phase Syndrome (ASPS), and this disorder increases with increasing age:
http://www.psychiatrictimes.com/sleep-disorders/sleep-disorders-elderly
Ahhh—but is this a good thing or bad?
I’m seriously wondering about what will happen to me when I retire.
I’m 63, hate my stress-filled job, counting the months to retirement,and really,really dreaming of being “free”.
But I’m also really really worried about being free.
Sure,I have some interests that right now look like they can provide me and the spouse a couple hours of activity, a couple times a week.
But there will be times when I’ll end up with absolutely nothing on my schedule for a week or two straight.
I watched my parents in their retirement,and…just like the quote above,—was shocked at how they could stretch a simple haircut into a major event. So I thought “wow, I’ll never be like them”.
Just like when I was a rebellious teenager in the 60’s and thought “Wow, I’ll never be like them”. 
Turns out that, well,…I did kinda turn out a lot like my parents*.
And it looks like,to do it right, I’m gonna have to put a lot of work into planning for this gettin’ old thing.
*(I even have a lawn–and I dammit, just yesterday, I almost told some kids to get off it.)
When I was young, I could easily stay up until 2 or 3am and then sleep until 11am. Now that I’m older, I find I can still stay up until 2 or 3am if I had a decent night’s sleep the night before, but I can’t sleep in any longer.
I blame it on the fact that like many adults I can’t get to sleep (or go back to sleep) if it’s light out. And I have to get up every morning sometime between 6 and 7 to pee.
(To answer the obvious question – yes, our bedroom has light-blocking drapes so that room is dark. But the bathroom has skylights.)
We should compare notes in three or four years because this post reflects my thinking almost exactly. I’m 63, too, just without the stress-filled job (mine is pretty nice).
I am old and I go to bed at 1 AM and wake around 8AM , I have old neighbors that are up till 11 PM or later . Not all old people go to bed early ,and just b/c they are in bed it doesn’t mean they’re sleeping . They could be watching TV ,reading a book of having sex !
It’s called a work schedule. 
Get up at 5:15 AM, shave, shower, start the coffee pot, fix breakfast. Eat & drink coffee while listening to the headlines and weather on TV for 15 mins.
Out the door at 6:50AM. Drive. Settle into your desk chair by 7:45AM. Earn your paycheck. Get home by 6:15PM.
Repeat for 45 soul crushing years.
You don’t stop waking up early just because you’ve retired.
I used to get up even earlier when my daughters were young. It’s amazing how much kids can slow you down in the mornings.
The only really good thing about retiring (involuntarily) early is that I no longer have to get up at 5 am as I did for all of my working years. I am a confirmed night owl and remained so despite all of society’s pressure to change me. Typically, I go to sleep about 2 am and wake up at 7 am. I am still getting the 5 hours of sleep I always have, but at hours much more convenient to me. And you won’t see me at the early bird restaurant specials for seniors. I eat dinner around 9 pm.
Never really noticed the sleep/wake habits of older generations, but if it comes down to driving slow (10 under) and careless, that’s a different story.
I’m 29, but have been trying to change out of being a night owl for 10 years, it just won’t happen. That being said once I get older, I will definitely figure something out in order to milk every last hour of being conscious. I’ll probably be one of the types to say “i’ll sleep when I’m dead”.
Old fart reporting in here.
I generally get ready for bed around 10 (after the end of the two hour jazz show) and then read till 11, turn out the light and go to sleep. If I get up to pee before about 3 or 3:30, I will go back to sleep. Later than that and I likely won’t. Regardless I am likely to be up by 6. My wife generally turns out her light at midnight is up before 7. But we have two sets of friends who follow an 8PM to 3 or 4AM schedule, so I am familiar with the phenomenon and cannot explain it.
This describes me to a T. No matter what time I go to bed, I wake up at 3 a.m. and cannot go back to sleep. This makes me exhausted by the end of the day and I’m falling asleep by 7 p.m. My mom and my sister were the same way, and it gets worse the older you get.
The only thing that breaks the cycle is when I occasionally take a Lunesta. This enables me to sleep all the way to 5:30 or so, and then I can stay up to an adult bedtime.
It sucks.