1. Start with a hypothesis, that "dark mode is less comfortable for me than light mode".
2. Design an experiment: find the sites that you use most. Use them for 10 minutes each in light mode and dark mode. Write down your impressions.
3. Build a conclusion: was your hypothesis correct? Was it partially correct for some sites?
Then you can adapt your behaviour according to your new, Scientifically-proven knowledge.
Science isn't faith-based, but there are a ton of problems with Academia and the way Science is practised and published at the moment. Science is also not connected with Academia - the scientific method doesn't need a university grant to work. You can literally conduct your own experiment in a couple of hours (as above) to get better information than any study. Not publishing it doesn't make it any less scientific.
It makes no sense to me to trust an unknown number of studies over my personal experience. I prefer dark mode. I'll stick with that. You do you.