Agreed. It’s possible the improvement is due solely to a reduction in total light output (which I assume is a side effect of reducing blues) but something about it really seems to help. I still wish my monitor could go dimmer.
This is a very dangerous idea to have. Placebo is a very well known effect.
To be very clear, you can test for the abscence of an effect. It is a little bit more challenging than finding a "true" effect, but it is feasible.
It is a dangerous, and common, misunderstanding to not distinguish between "no significant effect" and "statistically significant zero effect".