Diagnosed with ADHD but not at all a night owl. After a day of procrastination I'd rather go to bed at 6pm and get up at 2am to work than trying to get anything done in the evening.

I might be an outlier but I feel the time of day when I can focus best and my general ability to perform tasks are independent of each other.

But there might also be some selection bias on HN. I have the feeling that in tech night owls outweigh early birds more than in other areas (maybe except for designers).