Hi, I am just a random nixos user.
I also suffered from similar issue when I upgrade from 24.11 to 25.05
Maybe you can test removing this line
videoDrivers = [ "amdgpu" ];
if you also have "amdgpu" in boot.intrid.kernelModules, also try removing it.
It even prevent me from booting into stage 1.
There is the reason why I tried disabling “amdgpu”:
My machine working without these 2 lines, but YMMW.