Why not stand it down, at least temporarily as a show of support for the airlines and airport ?
How many flights are wanting to come in during the curfew at the moment? Temporarily lifting the curfew when no one wants to come is not sending a message to anyone. Are SYD knocking back international requests because they are outside hours? There's no overseas tourism, curfew or no curfew. Aussies can't leave, arrivals get locked up for 14 days.