The problem is, that many of the developers are mistaking the Dark mode with BLACK mode (like Opera GX, Telegram's night mode, Android's [MIUI's] dark theme, and similar themed applications). Dark mode - as with Discord - is really about having the contrast _reduced_ and overall making the whole experience more dark greyish, which reduces strain on the eyes. Try this with BLACK instead, and you'll start to cry after a couple of minutes (yes, I know, I'm old and grumpy..). The very popular dark themes, like Monokai are popular exactly because they respect these very simple rules: 1. dark does NOT mean black, 2. reduce overall contrast.
I personally HATE the fact, that with Opera GX for example, you don't even have the _ability_ to choose if you would like to use the Dark mode (which is, again, BLACK mode in reality).
Contrast can stay, for me "dark mode" or 'night theme' is about reducing the overall luminous intensity.
My own belief is that when a sea of white is removed the need for 'crisp black' to stand out against it is also reduced; this might relate to a different perceived contrast due to the lowered noise floor (far less photons being rejected, so it's easier to pick out the desired ones).
At least some of us prefer a Dark mode that especially uses real black in backgrounds because of OLED and other HDR screens. Real black on many OLED devices is an entirely unlit pixel. That's very plainly less light being forced at your eyes from that screen, and absolutely will reduce certain forms of eye strain. Black backgrounds literally fade into the background of the screen. Grays and dark grays don't do that, they need at least a little lighting.
As with almost all aesthetic preferences, your mileage and your hardware may vary.
