If something apocalyptic should happen, Bitcoin will be the first to kick the bucket since it doesn't take much to bring down the network. But without Internet Bitcoin is as useless and worthless as the dirt under your fingernails. In fact, just disrupting the Internet integrity for a long enough time (say, a few months) will most likely suffice to check it out. Paper money seems to be more resilient and durable in this respect and may last a little longer after governments disband and disperse...
But ultimately all paper will burn
Internet might indeed be some sort of a bottleneck, but that just shows that spreading all mining farms and nodes around the world is a very important aspect. If you look at how many farms are hosted in China, then it would be an easy thing for the Chinese government to pull off the same blocking action that they do with various social media platforms and all kinds of other sites. But the operators of these farm are only interested in the financial aspect instead of looking how to decentralize Bitcoin even further...