Can 220v touch shock an insulated person?
If you have a 3 phase star mains system then there is always a common ground ( the to earth connected center on the transformer)  and therefore a way of the current to pass from the touched phase trough the body to earth.

In a 3 phase delta mains system there is also a way for the current to pass but this time it is trough the body, the capacitance of the transformer and a different phase on the transformer.

When we have a frequency regulator the above can also take place with the same motivation.

Birds on a HV line can get hurt by lightning because a current can flow from the lightning bolt to the HV line. This in a capacitive sense or when the surge arrester gets activated. Anyway it will kill the bird.