I thought I heard the airfield controller say there were 400+ and that they expected 50+ from Southwest soon. My first thought was about the concentrated value

I thought I heard the airfield controller say there were 400+ and that they expected 50+ from Southwest soon. My first thought was about the concentrated value and something like an earthquake or a plane crash. My second thought was "how long would it take to replace one of these planes?" but I guess an airline could replace it within hours due to the Boeing delivery backlog, but likely won't need to because of the lack of demand for travel right now. Not a trillion, but still expensive.