Exotic plants are not native. They are from someplace else. Yet, most plants within most home gardens are exotic. Most are capable of tolerating the more extreme climates from which they originated.
Some tropical or subtropical plants actually prefer milder climates. After the recent cool weather, some vulnerable plants exhibit symptoms of frost damage.
Vulnerability is relative though. Honeybush and elderberry can be mostly evergreen with minimal chill, or deciduous with more pronounced chill. Both tolerate more chill than they can experience here.