This is part of the reason that long-haul LCC carriers have struggled. They can’t get the utilisation up without falling foul of curfews and where they can, the flight times are unattractive and yield is pushed down.
The low-cost LCCs are left with a difficult problem to solve, their new 787 fleets are expensive to lease, they have lots of seats to fill, curfews and time zones are what they are. Air Asia X have already chucked in the towel and are now focusing on high demand mid-haul routes.