"Faulty data submitted by 3rd party (French airline?) wreaked havoc!"

Yeah, sure. Blame 3rd party while your system didn't sanitize input enough, or was tested only with valid data vs. fuzzing (if only to help determine how to handle invalid input).

Quote from the UK’s air traffic controller’s CEO particularly caught me eye - this apparently isn’t some ancient component:

“Rolfe has been asked about delays to investments in new systems.

He said Nats invests £100m a year, and the piece of the system that failed was replaced only five years ago.”