Bind mounts. I've never bothered to figure out named volumes, since I often work with the contents outside Docker. Then I just back up the whole proxmox VM. (Yes I'm aware proxmox supports containers, no I don't plan to convert, that's more time and effort for no meaningful gain to me.)
You can restore that backup to a new VM. I just make sure it boots and I can access the files. Turn off networking before you boot it so that it doesn't cause conflicts.
Well, except for all the belt and road projects that they expect to foreclose and repossess. https://dailymare.com/news/chinese-firms-now-control-over-a-third-of-africas-ports---raising-fears-of-beijings-expanding-global-reach,1269
Ever play Civilization? There are more forms of victory than military. The US is going for cultural, China is going for economic.