We truly live in a golden age of terminal emulators.
I still remember how essentially nothing happened in the terminal world from the late 90s until a few years ago (other than iTerm2 on macOS), and suddenly we have Kitty, Alacritty, Foot, and Wezterm, each developed independently of the others, and each of them better than anything that came before. It's amazing to watch these projects evolve.
If tmux control mode was ever implemented for kitty I'd use it, but Goyal hates multiplexers so he refuses to do it.
Luckily it looks like wezterm will have support eventually.
I've stared at the comparison image between MacOS and Kitty and the only thing I can tell is that Kitty is displaying the colored text in a very different way - frankly, one that is harder to read on account of being lower contrast.
In plain English, can someone explain what's going on, and why anyone should care?
Getting fonts to render correctly is a difficult task. Compositing in linear color space is the visually correct way to blend colors. But in practice no platform renders and composites fonts in linear color space, and each has opinionated approaches to how fonts should be rendered. Font designers can design a font with a specific platform in mind, that on another platform looks terrible. And people who spend all day working with a terminal can be very picky about how they want text to look. The latest release of Kitty provides tooling to allow tweaking the compositing settings so that any font in any color, can render as desired on any platform.