This site seems way outdated, not just in terms of style. It suggests Chrome as an open source alternative to Firefox, but also that Firefox is an open source alternative to Internet Explorer 7.
Modern monitors can output 1000 nits, which is super bright - same with cars. When I was young I sometimes saw yellowish headlights, which weren't bright enough, but now we have LED and Xenon lamps that burn the cornea from your eyes.
I've always been a dark mode user where possible. White screens are just exhausting to look at. I'm 23 so I'd hope age hasn't affected me that much yet xD
Personally I see dark mode as an accessibility option and I specifically avoid services that do not have dark mode.
Sadly, work still uses stuff that doesn't have dark mode so after a work day my eyes are so tired.