I now it's fashionable for people to write all sorts of disparaging remarks about Russia, generally done by those who have not visited or even have knowledge of the country, but this sort of stunt as pulled by the Amsterdam slot "co-ordinator" really hacks off those from countries which have no restrictions on carriers coming the other way, and notice carriers from those countries appear able to change and flex schedules, and add services, at their home base without difficulty.
If KLM mounted exactly the same cargo operations and flexibility as ABC do, they could do so without restriction because they can pool all their flights to get the 80% overall figure. It just picks off carriers from other countries and gives the home team an advantage.
It's not as if Amsterdam has a shortage of runways, is it ...