Prevent CSS/JS loading when plugin is not used

You need to use action wp_enqueue_scripts except wp_head like:

function inf_remove_junk() {
    if (!is_admin()) {
          wp_dequeue_style('js_composer_front');
          wp_dequeue_style('js_composer_custom_css');
          wp_dequeue_script('wpb_composer_front_js');
     }

}

add_action( 'wp_enqueue_scripts', 'inf_remove_junk' );

But it remove the scripts from front end.

1. I think on archive pages VC does not execute it’s shortcode. So you can check is_archive() condition instead of is_admin().

2. Or you can check the shortcode from content and remove assets like:

   function inf_remove_junk() {

   // 1. Check shortcode exist in post content and disable scripts.
           global $post;
           if ( stripos($post->post_content, '[YOUR_SHORTCODE]') ) {
   
   // or
   
   // 2. Disable scripts on all pages except single page, post, custom Post etc.
   
           if ( ! singular() ) {
   
   // or
   
   // 3. Disable on archive, 404 and search page
           if ( is_archive() || is_404() || is_search() ) {
                 wp_dequeue_style('js_composer_front');
                 wp_dequeue_style('js_composer_custom_css');
                 wp_dequeue_script('wpb_composer_front_js');
            }     
   

   }
   add_action( ‘wp_enqueue_scripts’, ‘inf_remove_junk’ );

Also, For premium plugin support you need to contact plugin author for better answer.