Which colour scheme is better?

> Of course, I adjust my overall monitor brightness according to the ambient light (so do not use full brightness in the evening).

I suspect this may actually play a significant role here, since "light themes are way too bright / blinding / etc." is a common reason for the preference for dark schemes, and hints at incorrect monitor brightness settings.

As a rule of thumb, indoors in an office space around 100-150 cd/m² are the right ballpark. This corresponds to a brightness setting of around 20-30 % on most screens. In the evening with a little bit of bias light 0-5 % are usually the right area, though too bright on some models.

I'll basically repeat my comment from below, but ergonomically set up displays meet ambient brightness, but don't exceed it (much). If you're sitting in front of a display set to 80 % brightness (~300+ cd/m²) in the evening, you're simply holding it wrong and compensate by limiting the content to dark tones only, which is a crutch at best.

That's not to say people shouldn't use dark themes. But if the reason for choosing a dark theme whenever possible is mostly "white is so bright it literally hurts my eyes", then the environment is decidedly wrong and needs fixing.

Dark background during the night, and light background during the day, in most cases.

As simple as that.

I wish my text editor would switch automatically and I might write a script to do that at some point, but this is a minor annoyance.

However, I do notice that "because science says so" is becoming a more and more common "you are not allowed to argue with my conclusions" kind of add-on to any assertion. It is an oddly religious, faith-like use of the word "science".