Blue light has no effect on eye strain[1]. The sky has about 100x the blue light emissions than your screen. It might be a great placebo effect, or maybe it just decreases brightness of the screen.
Had you really considered what I wrote you wouldn't have missed this important bit: "when I turn off the Low Blue Light mode I can instantly feel the strain on my eyes. The picture is gorgeous but it's too bright and intense for work."
So, the feature also dims the brightness, and I did this with my other monitors too so they matched the BENQ monitor I said has this feature.
I think this is something people commonly conflate.
These two things are true: 1. screens cause eye strain, 2. screens make it harder to sleep because of blue light. People then mistakenly interpret this as "screens cause eye strain because of blue light".
It's a bit frustrating how many blue light filters advertise themselves as reducing eye strain, exploiting this misconception.
So, the feature also dims the brightness, and I did this with my other monitors too so they matched the BENQ monitor I said has this feature.
But it's more fun to be dismissive, right?