The default period for locks is 1 hour. That makes a lot of sense for content disputes and offtopic comments. After a short period of time, the people who are engaged in editing or commenting will move on to something else. But historical significance questions are not going to be unlock-worthy after any period of time. I can't think of any reason to unlock such questions short of a complete turnaround of site culture.
Can we make the default for historical locks be forever rather than one hour?