Yes, you can delete the Printable Colors. This is how you could do it.
In this article, you will get to know if the printable colors can be deleted from the edit page and if it can, how it is done.
Login to Backend
Navigate to Product Designer -> Manage Printable Colors.
You will land on the Manage Printable Colors page, where you have to click on the Edit button on the Action Column. You will be directed to the Edit Printable Colors page.
In this page, on the top right corner there is a Delete option, by clicking here a pop-up will appear that makes sure if you want to Delete or not. Click “Ok” to confirm and then that particular printable color will be deleted.