While you are right to ward off this person's paranoia and we really shouldn't be completely freaking out about light exposure from our phones and such.
I think you are minimizing the issue. We wear sunglasses when it is bright (and should as it can be harmful to our eyes), we don't stare directly at the sun, we don't have it anywhere near as close to our faces, and we don't have the sunlight at night which adds another 2-4 hours of exposure to blue light.
There would appear to be more intense blue light in an LED than coming from the sun.
This page while not a particularly good primary source has some comparisons of the intensity of the blue light in LEDs vs sunlight.
https://iristech.co/pwm-flicker/
"The use of blue light is becoming increasingly prominent in our society, and a large segment of the world population is now subjected to daily exposure (from a few minutes to several hours) of artificial light at an unusual time of the day (night). Because light has a cumulative effect and many different characteristics (e.g., wavelength, intensity, duration of the exposure, time of day), it is important to consider the spectral output of the light source to minimize the danger that may be associated with blue light exposure. Thus, LEDs with an emission peak of around 470–480 nm should be preferred to LEDs that have an emission peak below 450 nm. Although we are convinced that exposure to blue light from LEDs in the range 470–480 nm for a short to medium period (days to a few weeks) should not significantly increase the risk of development of ocular pathologies, this conclusion cannot be generalized to a long-term exposure (months to years). Finally, we believe that additional studies on the safety of long-term exposure to low levels of blue light are needed to determine the effects of blue light on the eye."
Basically, we shouldn't go out of our way to expose ourselves to excess blue light if we can help it. We don't know what it does entirely. Its not worth losing your mind over either but its not quite simple as 'the sun is blue. you'll be fine'
its not so much 'sussing out tricks' as a blanket ban on anything that can be abused. My parents made roughly 100k when I was going to school but they were terrible with money and have a lot of children. The 'expected contribution' was actually quite high but I never received anything from my parents at all. Thus, I have much in the way of student loans.
Not to take away from your point but the colleges having to work against these sort of tricks has a lot of unintended consequences.
I actually looked into this recently and found some articles(which I have since lost) that explained that it would appear that the delta between blue light in the morning and at night is the mechanism by which our circadian rhythm seems to work.
However, working with the idea that blue light is photo toxic, it is most likely better to reduce your blue light at night rather than increase it in the morning.
I wanted to do this experiment with dosing myself with blue light in the morning but I abandoned that after seeing research on photo toxicity
Perhaps establishing a morning habit of going and standing in front of an east facing window might be a worthy experiment?
Other religions that have kept their popularity and adherents over the centuries(and much in the past century) have, part, reformed and toned down the significance of these violent mythologies especially in their relevance to doctrine.
To assert otherwise seems like arguing in bad faith.
if you pay them better they won't leave. But you've basically said that even after training they are worth less than someone you hire in at first. This distinction is why people leave. You trained these people in the way you'd like them to work, Tailor-made to your processes but you still say they aren't worth the same as the people you hire-in. No wonder they leave and go some place where they've now been hired in without needing to be trained. If you don't value your own training highly enough to pay these people the market rate, what reason do you expect them to stay and work for you for?
Do you not see how there is value in having someone who is trained to your specifications? You're still getting labor out of someone but when they move to being a proper dev you don't have to worry about any training issues because you trained them.
I truly doubt you hire developers who are productive from day one, when your mentees will be productive from day one as a real dev AND will probably have less growing pains from having learned bad habits or a different standard at another company.
how does basic physics tells us there is no free will? That is generally an argument about hard determinism which could be argued is invalidated by The Heisenberg Uncertainty Principle.