This is kinda clickbait - all of the research mentioned was not 'research' at all - all the articles mentioned by the OP as "studies" (apart from the battery section) were from NN, or Nielson Norman Group, which were opinion articles by authors employed at that company lightly referencing a few studies. It's all highly subjective and opinionated at best, and "ain’t all that" is about the best we can say on this subject to date. Research doesn't suggest much at all, except you save battery with dark mode on OLED screens, that at least is conclusive.