See, this is the kind of bad argument that really irks me. There are good arguments about how computers aren't ready to replace pen and paper for actively doing math, and even a few shortcomings for computers replacing paper textbooks. But "actively blasting light" doesn't mean anything. Photons are photons. If you think a backlit display is somehow harder on your eyes than an indirectly-lit piece of paper, then you should be trying to figure out whether you simply have the backlight set too bright for your surroundings, or if your screen's contrast ratio at reasonable brightness levels is inadequate. Your LCD's default settings are probably optimized for movie-watching more than reading, but that's easily fixed and definitely not an inherent limitation of all backlit displays everywhere.
This may be true, but in my experience(not very wealthy, typically sub $400 devices) the presets are set such that 0% backlight in the OS is glaringly bright. I cannot turn it down without rooting the device.
Color temperature can also be a problem, but there's a lot of awareness of that issue nowadays. Most operating systems now support automatic adjustment of color temperature based on time of day, plus manual adjustment. Devices that adjust their color temperature to account for ambient lighting are starting to catch on, and I expect they'll be pretty common in a few years.
And what Grad student can afford those at [Insert State University]. I was a PhD student in math not long ago, and vastly preferred paper books, and even printed out articles. It is way way easier on your eyes than something actively blasting light. Maybe in 20 years high quality e-ink will be cheap enough, but that has been promised since forever.