> every site suddenly went full dark mode because the iPhone finally got an OLED panel, accessibility be damned.

Offering only one color scheme, light or dark, is not accessible. Light sensitivity is just as real as astigmatism.

I know, because there was a teacher at my high school who had prescription shaded glasses for his condition.

Screens emit less intensive light than ambient on a cloudy day. The teacher in question couldn't even go outside without his glasses.

> couldn't even go outside without his glasses

Yep. The term for this is 'dayblind'. My sister has a friend whose light sensitivity is so severe that she can't even look up at night when there's a full moon over clear skies.

I don't know if she has any sunglasses with prescription tint, but she does often wear multiple pairs of sunglasses at once (stacking fitovers of various sizes). She also wears sunglasses whenever she uses the computer.

I forget what condition my sister's friend has, but she's legally blind. Extreme light sensitivity is often a feature of retinal diseases that also cause other visual acuity problems.

Yep first thing I do when I find a dark default site is try(uselessly usually) to find an option to switch it to light mode.

I think companies should deliver a white and dark option always.