HTML error in frontend, robots noindex suggestion

Found an HTML error in frontend in file template.php in line 357:

<sec class="right-section full_screen_mode" ...

Should be like this:

<section class="right-section full_screen_mode" ...

And would suggest for Google etc. to set robots to noindex if plugin shows the under construction template in frontend, maybe add code similar to this in template.php at about line 24:

$this->remove_header_tage_run_hook();
add_action('wp_enqueue_scripts', array($this, 'inc_js_file'));
add_action('wp_enqueue_scripts', array($this, 'inc_css_file'));

// suggested fix: override any other robots values
add_filter( 'wp_robots', function( $robots ) {
	return array( 'noindex' => true );
}, PHP_INT_MAX );

Another possible solution here would be replacing the WordPress HTTP status 200 OK with 503 Service Unavailable and a Retry-After value.

Currently search engines etc. will happily index the under construction message for any already known page if additional extra settings in WordPress or SEO plugins etc. do not prevent that.

WP Maintenance Mode & Site Under Construction 4.4, WordPress 6.x