Well, I’ve tried three different types of builds in single player to experiment with that concept.
In the Maelstrom zone:
Tier 1 - totally ripped to shreds; Tier 3 - lasts longer, but storm and monster damage still destroy it.
Edge of the Maelstrom zone:
Tier 3 - During the Maelstrom, the winds still pass through the walls and the sounds of the howling winds are loud for an indoor base. So the base stands and monsters don’t visit, but the environmental effects made it fairly unpleasant for a “home.”
Away from the Maelstrom zone:
Tier 1, 2, 3 - During the Maelstrom, the area gets darkened and there is some wind. But there is no howling wind and the area is still mostly pleasant (though gloomy – too gloomy for my liking). The Funcom art department made a beautiful map and then shroud it in gloomy darkness most of the time - I don’t get that. But that’s not my call.
The area away from the Maelstrom is too quiet. And yes, since there’s no Purge, there’s no reason in PvE to have any base defenses or walls or anything to protect you because you never need it. You don’t even need figher/archer thralls or pets or traps or even so much as a fence. And that animals that spawn nearby are tethered on a tight leash to stay in their spawn areas, so they won’t wander to your base either.