I got a very helpful response about the problem at ESSA, see link below
I would never be disgusted, this is a voluntary network and you can only have admiration for all the ATC sparing their time, I’m sure no one does this on purpose, I have flown on Vatsim for 15 year now and only feel gratitude
This is due to flow restrictions that were in place which restricted the flow of planes from Poland to Sweden due to too much traffic for the controllers. This basically means that people will not be able to depart in whatever interval, i think they had 8 minute departure interval in action