The biggest takeaway people should have from this video is that a modern nuclear strike is effectively an overwhelming Denial of Service attack against emergency services, infrastructure, and supply chain... all at once, on an immense scale.
Enough so that quickly scaling a "proper response" just isn't possible. Even if just a single large city (500K+ pop) was hit with a single, typical modern warhead (200-300kt), the results would be covered in history books for the rest of the millennium.
A large scale exchange? The best you could hope for is that you're living in the Southern hemisphere to avoid the immediate horror, though the next 20 years would still be horrific.