Maybe for tech device things we should have two separate tracks, one for wealthy snd people who can modify devices and one for poor and people who cannot. Even my Thnkpad laptop under Ubuntu has a setting for 10% brightness which is far too high for a truly dark room. The next lowest setting is 0% which is absolute dark. How do you use your laptop under such conditions?

You could use xbacklight to have a finer control of the display brightness. You can also rebind the brightness keys to shell scripts that use "xbacklight -inc <percent>" or -dec, with a finer resolution.

I don't see how backlight settings for a truly dark room are relevant here. I've been annoyed by several of my devices being unable to dim far enough, but never in a situation where I would expect to be able to easily read words printed on paper. An office or classroom setting that has adequate light for pen and paper work could be too dim for an LCD at 100% brightness to be comfortable, but almost any device can be dimmed enough for that environment.

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.