15 years ago, I moved to NC, and they had the coldest winter in like 30 years. I was in corporate housing with my wife. It was so cold on the inside that we slept with multiple blankets and long johns. When I asked about it, they said all of the apartments had heat pumps and that was the best that they could do.
If the construction quality in NC is anything like what I’ve seen in VA:
1)They probably forgot to install insulation in one or more places.
2)They didn’t bother to seal up any of the gaps and cracks in the building.
So what you end up with is a poorly insulated, drafty piece of crap.
No heatpump works well in that situation, and a gas furnace will just run longer and cost more.
Though I am wondering why the aux heat for the heat pump didn’t turn on when it couldn’t keep up. Perhaps that was jacked up too?