I’m not a night owl. Although it seems to me that if a night owl wanted to live @thorny_locust style, a “clock” of any sort is still irrelevant.
Sleepy? Go to bed. Alert? Get up & do stuff. Hungry? Eat.
Most of us manage our other bodily functions that way: when the urge strikes, satisfy it / yield to it.
Running our sleeping, waking, eating, and other activities according to a similarly simple: “If you feel like doing it now, then do it now, no matter what ‘it’ is” rule would probably be a lot healthier for all of us. It’s what I’m drifting towards as work winds down.
After I retired, I found I was only eating two meals a day, for example. I’m no longer slotted into mealtimes that are more-or-less set up by someone else.