Which is why a properly earthed a 'whole house' protector must exist. Since that 5% is routinely made irrelevant when a surge is earthed BEFORE it enters a building. Since direct lightning strikes without damage is routine (even over 100 years ago) when a proven 'whole house' solution is properly earthed.

Damage from direct lightning strikes is so routinely averted that damage is considered traceable to human mistakes. One major mistake is to buy protectors that 1) do not even claim to protect from the potentially destructive 5%. And 2) do not have the always required low impedance (ie less than 10 foot) connection to single point earth ground.

Protection means a surge must not be inside a house. One inside, it will hunt for earth ground destructively via appliances (even if powered off). Plug-in protectors can even make that damage easier.

So that a follow-through current does not exist, a homeowner should also inspect his 'primary' protection layer that the AC utility is responsible for maintaining.