Generally we use Withdrawn option if we want the rule to be deleted from an application or move a rule to another class or ruleset. If the rule is stored in an unlocked RuleSet version, it is easy to delete it (and recreate it in the appropriate place, if desired).
However, if the application has been moved to another system or the rule is in a locked RuleSet version, it is no longer possible to change or delete that rule. Instead, the rule must be withdrawn.
So if we want any rule to be deleted/blocked we will create another rule in higher version and mark it as withdrawn as explained here. So there is no point of deleting the withdrawn rule as its usage is to delete/block the original rule.