The July 2024 IT blackout: what should managers take from it?

On 19th July 2024, the global IT structure experienced a partial collapse after the Crowdstrike company released a faulty update to its software. Some airports suspended flights, a number of media outlets were unable to broadcast, and many manufacturing companies temporarily halted production. What did this mini-blackout show and what lessons do they offer managers about crises and how to prepare for them, not only in IT?