Back in the late 1970’s and early 1980’s I worked as a control system engineer designing industrial control room consoles. We had access to all of the latest ergonomics and human interface research done by multiple different organizations. The dark print on light background was unanimously concluded to be the best for being easily readable and minimizing eye fatigue for operators staring at screens for long hours. And, the new generation of CRT displays were capable of doing this. This is why Xerox PARC went with paper white displays, and later when Apple appropriated this technology, they did the same.
As with a lot of things that Apple and other computer companies have unleashed on the unsuspecting user, dark mode is another flashy “must have” gimmick. I have no use for it myself. However, software developers have to keep in mind the demands of their users, and if users think dark mode is the best thing ever, and are happy to ruin their eyesight, then the developers will have to give them what they want.