I can't see a really long term future for IAG - its really about managed decline to a smallish, principally business class, airline
But if the Iberia situation turns really nasty it will be curtains for a lot more of their staff than 4500 - it will accelerate the decline
Remember the UK miners - if they'd stayed in their jobs in the early 80's they'd still have lost a lot of workers but spread over a decade or two - as it was the axe fell very rapidly after their strike