It is worth noting that many key third parties are also struggling which adds to the customer facing airline bearing the brunt of criticism.

Yesterday my 16:20 flight from NCL to LHR was boarded and ready for push back before the flight crew were advised due to ATC staff shortages our slot would be for a 20:50 departure.

Happily the crew persisted with the "we are ready to go" and slowly earlier slot times were achieved (as they do, perhaps the FO should have kept us less informed about the extent of the possible delay!). We eventually landed at LHR at 19:11.

Lots of missed connections and more chaos for the airline despite this not being of their making.