The flat design trend is so tired, it never looked good, and it promotes bad UX/UI. That has always been my opinion and it has grown only stronger as more bandaids like 'dark mode' are slapped onto it.
Dark mode is an accessibility issue. Yes, flat designs can exacerbate the issue – white space being a primary design pattern – but having a dark mode version of something would still be desirable, even if we went back to skeuomorphic design.
This might be sarcasm, but if not:
Some highlights of counterexamples include... The Office Ribbon Winamp Windows Media Player Kai's Power Tools QuickTime Player 4 Geocities websites Flash websites
... and many more http://hallofshame.gp.co.at/
Design is much like politics right now, it's hilariously sad when there is no concept of moderation or a middle ground.
White-background designs are really just a hold-over from design approaches developed for paper. Whereas white is a default color for paper, it never was on CRTs, and isn't on OLED displays either. The design choice was mostly an implicit (or habitual) emulation of paper.
There are both hardware and ocular reasons why dark backgrounds are advantageous on screens, particularly mobile OLEDs. Power consumption, eye fatigue, contrast, durability, etc. We need to make some of these changes regardless of artistic design style.
In particular, dark modes may become more difficult as you get older. I'm 67 and I have a great deal of trouble reading text in a dark mode.
There is a physiological reason for this, and if you do any photography using manual aperture control you may be familiar with it. Very high quality lenses should be sharp whether the iris is wide open or stopped down. But mediocre lenses have trouble wide open and give better sharpness stopped down to a more narrow aperture.
As you get older, the lenses in your eyes are not as good as they were when you were younger. There is a benefit in sharpness to have your irises stopped down instead of wide open.
Light modes accomplish this. The background light naturally triggers your irises to stop down, resulting in a sharper and more detailed view.
Dark modes encourage your irises to open wider, reducing your visual acuity.
Of course many people do enjoy dark modes, so there will never be a way to please everyone! But please consider not making dark mode your only mode.
Anyway, dark backgrounds and dark interfaces can and did exist without participating in the flat design trend.
Still, simple enough to solve that by cranking the PWM frequency to 2KHz or 20KHz.
What I want to see is higher refresh rates to avoid apparent blur from sample and old.
Windows made it pretty easy to roll your own dark mode in the 9x days, and Kaleidoscope was around for Mac users.
With Kaleidoscope, you just double-clicked the scheme file in the Finder and _everything_ was themed, from window frames to buttons to fonts to icons, and there were practically no limits to what scheme designers could do. There were a lot of impractical schemes, sure, but they were creative, fun, and personal in a way computer UI hasn’t been in ages. Just take scroll through the tweets of this Kaleidoscope twitter bot for a taste: https://mobile.twitter.com/kaleidoscopemac