This is an alternative for the Drupal Core color module. In my personal opinion this is somewhat more flexible. The reason is that the generated css is not compiled as a file (could be added perhaps later if this would have clear benefits), but added as inline css.

Also the css works through rendering of a twig file with a theme function. Which gives more control from preprocess functions, and twig template overrides on a theme level.

The swatches and settings can be defined in the theme info.yml which is easier for a lot of themers instead of writing php.