diff --git a/wp-includes/class.wp-scripts.php b/wp-includes/class.wp-scripts.php
index f4277c8586..cc88455bc1 100644
--- a/wp-includes/class.wp-scripts.php
+++ b/wp-includes/class.wp-scripts.php
@@ -351,19 +351,6 @@ class WP_Scripts extends WP_Dependencies {
 			echo $cond_after;
 		}
 
-        $async_attr = '';
-        $defer_attr = '';
-
-		if ( false === in_array( $handle, $this->in_footer ) ) {
-            if( true === apply_filters( 'script_attr_async', $obj->extra['is_async'] ?? false ) ) {
-                $async_attr = ' async';
-            }
-
-            if( true === apply_filters( 'script_attr_defer', $obj->extra['is_defer'] ?? false ) ) {
-                $defer_attr = ' defer';
-            }
-        }
-
 		// A single item may alias a set of items, by having dependencies, but no source.
 		if ( ! $src ) {
 			if ( $inline_script_tag ) {
@@ -398,7 +385,7 @@ class WP_Scripts extends WP_Dependencies {
 		}
 
 		$tag  = $translations . $cond_before . $before_handle;
-        $tag .= sprintf( "<script%s src='%s'%s%s></script>\n", $this->type_attr, $src, $async_attr, $defer_attr );
+		$tag .= sprintf( "<script%s src='%s'></script>\n", $this->type_attr, $src );
 		$tag .= $after_handle . $cond_after;
 
 		/**
diff --git a/wp-includes/functions.wp-scripts.php b/wp-includes/functions.wp-scripts.php
index b900fa2b2a..3eefe4f903 100644
--- a/wp-includes/functions.wp-scripts.php
+++ b/wp-includes/functions.wp-scripts.php
@@ -389,46 +389,4 @@ function wp_script_is( $handle, $list = 'enqueued' ) {
  */
 function wp_script_add_data( $handle, $key, $value ) {
 	return wp_scripts()->add_data( $handle, $key, $value );
- }
-
-/**
- * Add 'is_async' metadata to a script.
- *
- * @see WP_Dependencies::add_data()
- *
- * @param string|array $handles Names of the scripts.
- */
-function wp_async_script($handles) {
-    if('string' === gettype($handles)) {
-        $handles = [$handles];
-    }
-
-    if('array' !== gettype($handles)) {
-        return;
-    }
-
-    foreach($handles as $handle ) {
-        wp_scripts()->add_data( $handle, 'is_async', true );
-    }
-}
-
-/**
- * Add 'is_defer' metadata to a script.
- *
- * @see WP_Dependencies::add_data()
- *
- * @param string|array $handles Names of the scripts.
- */
-function wp_defer_script($handles) {
-    if('string' === gettype($handles)) {
-        $handles = [$handles];
-    }
-
-    if('array' !== gettype($handles)) {
-        return;
-    }
-
-    foreach($handles as $handle ) {
-        wp_scripts()->add_data( $handle, 'is_defer', true );
-    }
 }