Yes, All username is unique and email is also the primary key to log in to website. If you have purchased a course that is linked with WooCommerce product, you will get a unique login username to check your WooCommerce My Account page to access order details and the same login will be used to access the course.
can customers on woocommerce use the same username to log in for a learndash course
Update on March 17, 2020