mysqldump creates conditional comments that lead to errors when restoring

Question

the mySQL Dumps created with mysqldump contain conditional comments like this:

/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `wp_commentmeta` (
  `meta_id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `comment_id` bigint(20) unsigned NOT NULL DEFAULT '0',
  `meta_key` varchar(255) COLLATE utf8mb4_unicode_520_ci DEFAULT NULL,
  `meta_value` longtext COLLATE utf8mb4_unicode_520_ci,
  PRIMARY KEY (`meta_id`),
  KEY `comment_id` (`comment_id`),
  KEY `meta_key` (`meta_key`(191))
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;
/*!40101 SET character_set_client = @saved_cs_client */;

or this:

/*!40103 SET TIME_ZONE=@OLD_TIME_ZONE */;

/*!40101 SET SQL_MODE=@OLD_SQL_MODE */;
/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;
/*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;
/*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;

They lead to errors when importing the dump back to the db because

@saved_cs_client
@OLD_SQL_MODE
...

are null. "Cannot set character_set_client to null" or similiar.

When I remove all these conditional comments the import is no problem and everything is fine.

My questions: Is it save to remove these comments or to force the import in case of SQL errors? Which function do these statements have?

I understand that some variables are stored and after all is done are restored. But Why?