I can offer some distro-agnostic observations . . .
Having swapped from one to the other some time ago on Gentoo, what I had to (re)install was the kernel (since I'd built it without those drivers), mesa, and some xorg-drivers stuff (which may not be relevant to you). Also, LLVM (ugh), because the AMD drivers compile stuff on the fly somehow and gcc doesn't have a usable AMDGPU backend. Or something like that. At that point, the system should boot well enough to bring up the GUI, and you can worry about vulkan and such after that. If you have an initrd, that may need to be rebuilt or replaced. Bootloader should be fine if it's the same kernel version.
Having the kernel drivers for AMD present in a system with an nvidia card shouldn't present any problems—without the hardware, the kernel won't even try to load them. In theory, you should even be able to have both cards in there at once (if your mobo has the slots) and blacklist the drivers for the card you don't want to use, but it isn't the safest thing to try.
I'd guess that the 1945 report was sound, although I haven't read it. Vannevar Bush was a bright guy who came within a hair of predicting the modern Web at around the same time. He almost certainly didn't mention AI in his report, since even expert systems and such were science fiction back then.
The press release and the modern report? Both total garbage, I'm sure, regardless of whether they were written by an LLM or an overworked intern.