Posting quiet hours would be about as effective as their posting of other rules.....i.e. it'd be ignored.

Without an on-site caretaker, people will do whatever they please, and expecting people to be courteous or respectful is expecting a lot.

Until hikers police each other and correct or admonish folks who are behaving improperly (and hikers simply won't do this), then nothing is gonna change, either at the Place or at other hostels.

People truly concerned about this have one real expedient: They can stay elsewhere, which is probably not such a bad idea.

Query to Walking Dude: At hostels where caretakers or owners simply aren't present, how on earth is anyone going to be corrected or banned?