Earlier quoted context omitted.
I'm sorry, but people who claim "they've made the switch" just don't get it. Agreed. At 46, and having been a night-owl pretty much my entire life, I'm skeptical that you can just "switch" to another mode. Maybe you can, through very conscious and focused effort, manage to adapt to what appears to be a "morning person" lifestyle; but I suspect that people who do that are ultimately just faking it. That said, I've nev…
Anecdotally, at 51 and previously thought the same as you, I'm going to disagree. I'm closing in on two years of getting up at 5:00 am and it doesn't bother me anymore. I never thought it would be possible for me to adapt, but so far I have and I have no intention of changing. Time will tell.
I've noticed it already in my 30s, I can no longer sleep in so easily and have to get up, even if I'm tired.
Unfortunately it is because older people tend to have poorer sleep quality in general (less time in deep sleep cycles) so that's a pretty big downside.