Why “Include Related Contact” is missing in-person security profile

This option was removed from the Person Security Profile back in Rel 12 for performance reasons. I can't find the exact release readiness documentation link, but this change was documented.  Please note the additional duty role that can be added.
"Include Related Contacts Option Removed from Person Security Profiles
Improve performance of person security profiles by including access to related contacts on an exception basis. They Include Related Contacts option does not appear for new person security profiles. In existing person security profiles, it appears only if currently enabled. To enable access to a worker’s contacts, add the Manage Contact Person PII duty role to the relevant job and abstract roles."

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