How to interpret the static voltage susceptibility table?
Neither, it describes at which voltages a static discharge will interfere with the normal operation of the device.

Depending on technology and internal measures against static discharge (ESD protection) devices are either more or less susceptible for static discharges.

Usually the smaller the manufacturing technology, the more susceptible the device is.

So if you are using some of these devices and know that your circuit will be under influence of larger ESD spikes, you should take external measures to protect your circuit from malfunctioning in a rough environment.

A typical datasheet will contain a rating for that specific device, usually for a human body model and a machine model.

For example:



(Taken from datasheet of STM32F401)

I'd say that you are better off using external devices to handle ESD, but I'm biased because I'm working in an industry where devices have it rough and are expected to run 20 years.