I disagree overall. I find it much less painful on the eyes to read in dark mode at night, even if there's no evidence for health benefits. I agree that dark mode as an additional UI shouldn't be an afterthought, and should be tested fully just like the main UI. Poorly-designed dark mode can be difficult to use because of things like bad contrast.
I think the point is that, after everything is said and done, there's no evidence that supports dark mode. Personal anecdote goes both ways. Dark mode usually has lower contrast ratio (gray-on-gray text instead of black-on-white), and that's definitely proven to be harder to read. The beyond-frustrating thing for me is that Windows 3.1 supported dark mode via system color palettes along with any other color customiza…
Also even light mode is often gray on gray, with backgrounds like #eee and text like #112 for example. The contrast is probably lower on average for dark mode, but it can still be designed well.