Display Media Attachment Count in the WordPress Pages List

/**
 * Add a Media Attachments column to the Pages list.
 */
add_filter(
	'manage_pages_columns',
	'alkesh_add_media_attachments_column'
);

function alkesh_add_media_attachments_column( $columns ) {
	$columns['media_attachments'] = __( 'Media Attachments', 'alkesh' );

	return $columns;
}

/**
 * Display the number of attached media files.
 */
add_action(
	'manage_pages_custom_column',
	'alkesh_display_media_attachments_column',
	10,
	2
);

function alkesh_display_media_attachments_column( $column_name, $post_id ) {
	static $attachment_counts = array();

	if ( 'media_attachments' !== $column_name ) {
		return;
	}

	if ( ! isset( $attachment_counts[ $post_id ] ) ) {
		$attachment_ids = get_posts(
			array(
				'post_parent'    => $post_id,
				'post_type'      => 'attachment',
				'post_status'    => 'inherit',
				'posts_per_page' => -1,
				'fields'         => 'ids',
				'no_found_rows'  => true,
			)
		);

		$attachment_counts[ $post_id ] = count( $attachment_ids );
	}

	printf(
		'<span>%s</span>',
		esc_html(
			sprintf(
				_n(
					'%d file',
					'%d files',
					$attachment_counts[ $post_id ],
					'alkesh'
				),
				$attachment_counts[ $post_id ]
			)
		)
	);
}