This is anecdotal but when I went to live with my grandparents for a summer, I hated every minute of it. They lived on a farm with no wifi. By the last week or two though, I realized I sorta enjoyed it. I was out like a light by 10 pm every day. I was getting more exercise etc. I had no reliable reason to stay up past 10 pm and my body seemed to adjust to what felt natural.
As an adult, I can say that if school started later, I would have just stayed up later. There was even a time in college that I would stay up till 4-5 am. Sometimes you would know a snow day the night before and I would tell my friends on the west coast that I could stay up even later. It was awful but I couldn't see it at the time. It took me years to fix. I now sleep around 1 AM which I still wish I could sleep earlier but I'll take it.
Yeah - and you can get away with bad habits until you can't. An ex of mine was very successful through her early 30s despite being out and partying late quite often. Then she joined Goldman Sachs where the bar is higher, and all of a sudden she was like "shit, I gotta go to bed early if I need to keep up."
He did once rack up a tremendous phone bill by using his phone at night, but I think he learned not to do that any more.
Going to bed in the evening isn't a solution to healthy sleep schedules: it's an accommodation to waking up in the morning.
Why do teenagers need to be waking up early? Since we know that most struggle accommodating an early rise, why not, as a society, accommodate a late rise?
I'm in favor of moving back start times but we should also better study and educate on the consequences of bad personal habits.