The terms "choose to" and "peak time" would imply that those are the most favored times, but the very concept of jobs requires that people wake up at those times whether they want to or not. In fact, the big peak in average waking times in June (when many people have vacations) seems to indicate that most people will in fact wake up later when they do have the choice.
That's not wildly outside normal ranges. The average recommended sleep for an adult is 7-9 hours, with up to an hour variance outside that still being within healthy ranges for some people.
No naps during the day. I just let go of my notions about how much sleep was enough, and started going to bed when I was tired and getting out of bed when I wake up. I do not use an alarm to wake up, and I do not get tired during the day, so I think I've settled on an adequate sleep schedule for my body.
> Most common time people choose to wake up: 6:00 AM
https://snoozester.com/The-Wake-Up-Time-Report.snooze
> The peak time for waking up is between 6 and 6:30am.
https://www.edisonresearch.com/wake-me-up-series-2/