>The "musical loudness war" is completely irrelevant and makes no sense in this context either. Turn your speakers down if your ears are hurting.

Recorded distorted sounds are still distorted regardless of your volume setting. Loudness war making people's ears hurt isn't solely due to the volume. If you can't tell the difference between piss poor mastering vs something properly mastered and being able to recognize them when you hear them is one of those "ignorance is bliss" things in life. However, once you can tell, you can't not hear it once it's present. The only way volume fixes it is when volume is set to 0.

But the problem with the loudness war isn't the loudness per se, but the loss of dynamic range: if everything is as loud as it can be, there is no room for emphasizing anything.

It's like, if you are always shouting, you can never raise your voice.

Which is exactly what is happening with full contrast websites: if everything is at max contrast, there is no room for emphasis.

Printed text does just fine using maximum contrast all the time, and bold and italics for emphasis.

Maybe for text specifically you're right, but we use screens for other media like pictures and video. If we have to tone down contrast to make high-contrast text comfortable, we are also reducing contrast of other media, and this loss may be significant.

Now, if we had reflective monitors (like e-ink etc) we could just be comfortable with maximum contrast text (like printed text). I think the display technology is a problem here.

(But still: there are some books with yellowish pages which I find more comfortable to read than ultrawhite pages. Maybe such lower contrast pages are more expensive or something, or not adequate for all lightning conditions etc)

There is room for emphasis: bold text, colors, different font, …