Genesis Framework: How to exclude a specific author from archive custom loop

You can do it with the pre_get_posts hook. In WP_Query there is an author parameter :

pre_get_posts hook :

function wpse_288986_remove_post_from_author($query) {
    // We have to check if we are in front and if the query is the main query
    if(!is_admin() && $query->is_main_query() && is_archive())
        $query->set('author', -2); // Where 2 is your user ID
add_action('pre_get_posts', 'wpse_288986_remove_post_from_author');

EDIT : This code goes into your functions.php file