Really depends on the hostel
Some are like "it's 10pm, so better shut the fuck up" and others be like "it's 1:30, the night is just starting - let's pump up the volume!"
But more often than not, it's the more chill kind.
Although there are still party hostels out there.
By now I'm probably also too old for that and appreciate a few hours of good sleep.
They do
But as it needs to go into their private pocket, they manipulate the market and already spare regulations, so they have a free go and cash in
Wouldn't help them, when the nation gets the many due to sane profit taxing and fraud investigations