I think the designers are coming from the CMYK world of newspaper printing and such, where, due to alignment issues, text must be printed using a separate black ink ("K" black) even though it could theoretically be produced by mixing Cyan/Magenta/Yellow. This is due to the difficulty of perfectly aligning three different color plates, as well as imperfections in the ink.

In printed photographs, on the other hand, all four inks can be mixed to produce a darker black than is seen in the surrounding text ("rich" black). Thus, in newspapers, the contrast ends up being higher in photos than in text.

But this is due to limitations of paper printing technology--none of this applies to computer displays, where R/G/B components are always perfectly aligned.

Even in digital media, you might want a 10000:1 contrast in photos, videos and games, but you only want 10:1 in text.

It's not reasonable to constantly change your monitor's settings, especially when you want to display both in the same document.

With HDR content, this is already possible, full brightness in an HDR video will be far brighter than #ffffff in css.

But even for regular media, this is an issue, which is why you should configure your screen for the maximum possible contrast and then reduce contrast of text in software.

If you set text to maximum contrast, you need to reduce contrast in your monitor settings, which then also affects photos (which you obviously don't want).

It's a lot easier for the user to reduce contrast than to increase it.

Decreasing dynamic range, increasing the contrast, is trivial. But once the dynamic range has been compressed, you can't get it back.

You can always tomemap towards more contrast, but never back towards more dynamic range.

> Decreasing dynamic range, increasing the contrast, is trivial.

How would I do this on MacOS or Windows?

Most people have one adjustment easily available--the screen brightness setting. This setting can decrease the contrast of pure black/white text, but it cannot increase the contrast of off-black/white text. Same with the Night Light setting on Windows 11.

> How would I do this on MacOS or Windows?

Ideally you'd create a proper icc profile for your monitor. The ideal way is to use a calibration device, but both OS have a wizard where you can manually adjust contrast and brightness and generate a profile out of that.

This can be used to both increase or decrease contrast.