In register_post_type, I can register a custom post type and set parameters, including rewrite. Based on https://developer.wordpress.org/reference/functions/register_post_type/#rewrite, if it set to true, then the rewrite for this type of post will be handled.

Then I add some rewrite rules for the custom type of post by invoking add_rewrite_rule in custom_rewrite_basic function.

However, on my tests, I find even I set rewrite to false, the rule set by add_rewrite_rule will still work, why?