Fire and flood insurance protect against discrete or regional risks whereas ransomware will potentially disrupt operations globally, and actually most private insurers won't offer flood insurance to large swaths of the US because the risk has been deemed to be too high. The US gov insures against coastal flooding at GREAT expense to the tax payer.

I wonder what the biggest company is that's totally dependent on a single location (or locations in the same flood zone) and at the same time is usefully insured against such destruction.

Ports?

Take out a port, and screw an entire region.