Well, the configuration and state in both cases is all over the place. I admit that since the move to push program directories to /usr and the XDG share/config directories the problem has been largely solved. I only shared my perception when I was learning Linux, which was right after Mandriva came out
All of these distros strive to solve the problem with having multiple versions of libraries and programs coexisting without conflicts, but Gobo took a different approach. What Gobo doesn’t do is the declarative system configuration. In Nix you don’t need to worry about breaking your system because you can easily restore the previous version of your config. In traditional distros you would need to set up package manager hooks to make snapshots and create snapshots manually every time before changing something in /etc