I find I can enter a flow state with work more easily when I feel like the world is asleep.
But the screwed up sleep cycles from years and years of this are starting to take their toll, so I've been trying everything I can to replicate that peace of mind during daylight hours. No silver bullet yet.
It's a different world and definitely has advantages. However, like you, I'm not sure it's worth the tradeoff of being horribly tired long before my usual bedtime.
In total, I think I still prefer getting up late and sleeping late.
There's less local news. There's nobody to call or text. There are no deliveries. Slack is quiet. My email is quiet. Our repos are quiet. The dev logs are quiet. My family is asleep so I know they're good. If I need a minute to think, I can sit on my front porch and not worry about being distracted.
Now that I have a young kid, it's really hard (and generally selfish) to work those hours. I miss it.
It's so bad that I've started to get anxiety every time I open my computer. I start to panic because I know a distraction is coming. It makes it so difficult.
It's probably frowned upon in some places, but when I _really_ need to focus (during daytime hours), I generally shut down slack, email, my phone, etc.
Generally, the teams I've worked with over the years have been amenable to this. I try to promote it with my teams as well: actual time off (no popping in while on vacation or sick), good sleep, time for focus, shutting off slack - especially when not working.
The last thing any of us need is to burn out because of notification overload. It makes us a stronger team if we're all healthy, well-rested, and able to get things done.
If people are up, I can’t lock in; there’s a constant distraction somewhere in my mind.
If I’m the only person awake in the house, I seem to hit flow state with ease.
Personally, I find I sometimes have trouble accepting good enough solutions. I want more structure, a better defined start. At night I can drop into a productive flow state with much less resistance, ignore many of the day-time wants. The hours run short; let's seize what we can from the waking hours. As well that "inspiration," I think there is probably a physiological barrier lowering that happens as we go into the night. As we recede from the gods' light, as it were.