The update to the 590 nvidia driver was supposed to upgrade to 595.
However, as the bug report linked below details, the i386 builds of the nvidia libraries like libnvidia-decode-595:i386 did not get built for releases older than resolute. So now 590 libraries like libnvidia-decode-590:i386 depend on non-existent 595 packages (libnvidia-decode-595:i386) which causes apt to bail on the update.
No i386 Builds in package (Noble Numbat)
Your solution is to either uninstall the i386 versions of the nvidia packages and then proceed to upgrade to the 595 :amd64 nvidia driver packages, or completely remove the 590 nvidia packages and switch to the 580 version which is a LTS branch and supported for longer.
Whether to upgrade or not depends on if you have an application, like a game, that needs the i386 versions of the missing nvidia libraries. If you have no such application, then upgrading to 595 without the i386 nvidia libraries is your best bet. Hopefully at some point in the future Ubuntu will provide the missing architecture builds for those packages. QA is a wonderful thing.
You could also install the driver directly from Nvidia, but you’d be on you own for updating it and getting support for it.