How can I make my lockout time stack?
This feature is rate limiting
 and is done to prevent Brute Force Attack

This being a core security feature , it can be changed at OS level ( if at all ) and certainly would not be possible  without root

While I could not find reference to PIN / password rate limiting, you can see the Compatibility Definition Document 
(CSD ) mandating that for finger print recognition, specifying the number of attempts and duration. See 
How can I limit the number of fingerprint attempts before fallback to other login type?