[KarlKemp]

There is an option "increase contrast" in accessibility, plus a slider to adjust the display contrast, plus a set of color filters for color blindness that can be quite useful even if you don't suffer any of the specific conditions.

[icybox]

Thanks! I'm aware of this. I don't know how to describe it properly - the old OSX icons, even the "lickable" control buttons in snow leopard look just right. It's almost like there's a black line around the icons, the saturation is right and also colors go right together. I don't see this in Big Sur or Monterey. It's just oversaturated pastels without clearly defined borders. Looked slightly better in dark mode, but I prefer light mode. Snow Leopard (https://apparelever169.weebly.com/uploads/1/2/4/9/124908212/...) vs. Monterey (https://scr3.golem.de/screenshots/2106/MacOS-Monterey/Apple_...) - random searches for screenshots.

[Wowfunhappy]

The increase contrast option in modern macOS increases the contrast at the expense of making everything ugly.

Aqua in OS X 10.9 and below are naturally designed with high contrast and tonal range in mind.