I always tend to fall asleep after midnight. 00:30 on weekdays where I have to force myself to get out of bed to get to work, 02:30 on holidays or self-employed periods where I can allow myself to follow a rhythm that's closer to natural. I am most alert between 18:00 and 01:00. I am barely able to do brainy work before 12:00, and have just given up on trying to force it. If I'm forced to get up early multiple days in a row, my rhythm will shift slightly, but it comes back after a few days if there is no pressure.

My partner is the opposite. She'll be almost comically tired after 22:00, but will normally wake up around 05:00 and be super alert in the morning. Sometimes even earlier.

On our natural rhythms, we will cover all but two or three hours of the day awake, mostly with one person who is alert and performs excellently. This would be ridiculously useful in a more dangerous world than modern civilian society, and it comes in super useful on days when the routine is out of the ordinary. An active holiday, long car trips, errands that need to happen on odd hours etc.

It's not a disorder, it's an adaption. At least unless it gets more extreme than our experience. If society doesn't fit, then screw society. Honestly. Make room for those who don't hit the median, please.