Why aren't airlines drastically cutting back their scheduled flights if there has been such a drop in demand?
> the table below shows that over 320,000 seats have been removed by airlines operating between the two countries through to the end of October
And given the focus is on summer flights that haven't happened yet, those cutbacks would largely be in the future.
The A380 was built to get around landing slot rules.
It may be that your question is fundamentally not based in fact. You ask "why aren't they doing X", as though it were certain that they were not doing X. This may not be the case. Airlines may indeed have adjusted their scheduling.
It may simply be that not enough time has passed for the shift to affect scheduling.
It may be that airlines view the current state of affairs as temporary. Airport gate spots are difficult to come by, and one airline cutting flights grants those gate slots to a competitor, so they may think it's more profitable in the long run to take the short term hit until the international situation changes via election, impeachment, natural causes, or conquest.