Hey,
That little bit of css is to set the colors for your primary color options in the theme options > basic styling.
There are some woocommerce specific classes referenced to make sure the colors all match through the site. Referencing some woocommerce classes (along with all your other styling classes) is not going to hurt your site speed and certainly not something I suggest you worry about removing. It’s only css, not javascript or anything that has to “run” on our site.
But if you would like to do that I can walk you through creating a child theme: https://www.kadencethemes.com/child-themes/
and using some custom code in your child theme to unhook the theme options basic styling. (which will mean you will need to control that with your own custom css).
I strongly suggest against this for update reasons but let me know if you need more guidance and I would be happy to give you the unhook function for the theme options css output.
Kadence Themes