Edit: Lol you meant design. I think dark themes work better no matter the niche. As for the second half of the thread title, I don't really advise people to make sites that promote black hat seo or any illegal activity but there's always going to be shady people both online and in real life that dark sites will never cease to exist. They typically just move off the surface web and onto the dark web, if they're very shady.
Pretty much most online learning sites or sites that have courses have a light palette to them, very few do dark or even mid colour tones.
The only ones I've ever seen that go for a dark palette are dark web/black hat teaching, and sites about hacking (in the 'breaking things' sense, not the 'hacking something together for fun' sense)
In an age where dark mode browsers are common, it should be possible to normalise this somehow.
Edit: Lol you meant design. I think dark themes work better no matter the niche. As for the second half of the thread title, I don't really advise people to make sites that promote black hat seo or any illegal activity but there's always going to be shady people both online and in real life that dark sites will never cease to exist. They typically just move off the surface web and onto the dark web, if they're very shady.
It's nice to hear people that are more open minded. Anyway, though, I like my design I have now. It's grown on me, but my original wish is always dark.