There’s another aspect to this. Suddenly, a lot of inbounds have to find somewhere else to go. With LTN/LGW/LHR all running at 95%+ capacity they soon fill and start to refuse diverts.....which then places additional strain on ATC, in some of the busiest airspace in the world, if aircraft start to declare Maydays due low fuel. I appreciate that can happen at anytime due to a closed runway....but if it’s a situation that can be avoided?
Bus fire, outside landside, and as a result you are denyed one of the major SE UK airports.......From the POV of an aviator who sometimes has Stansted as the only planned alternate inbound I think that is probably the most important question..