Nvidia NVML Driver/library version mismatch: dkms, modules, drivers and modinfo versions - nvidia

Question

I have the Nvidia NVML Driver/library version mismatch error, for which I recommend reading the following answers:
https://stackoverflow.com/a/67105064/1782553
https://stackoverflow.com/a/71672261/1782553
However, after purging and re-installing the nvidia packages (necessary because of the issue described here), I still get the error. A reboot resolved the issue but I'd like to understand why?
Also, I'm not sure I understand the meaning of the 4 following commands and the Nvidia version they display.
Before reboot
$ cat /sys/module/nvidia/version
515.65.01
$ cat /proc/driver/nvidia/version
NVRM version: NVIDIA UNIX x86_64 Kernel Module 515.65.01 Wed Jul 20 14:00:58 UTC 2022
GCC version: gcc version 9.4.0 (Ubuntu 9.4.0-1ubuntu1~20.04.1)
$ dkms status
nvidia, 515.65.07, 5.4.0-131-generic, x86_64: installed
$ modinfo nvidia | grep ^version
version: 515.65.07
After reboot
$ cat /sys/module/nvidia/version
515.65.07
$ cat /proc/driver/nvidia/version
NVRM version: NVIDIA UNIX x86_64 Kernel Module 515.65.07 Thu Sep 22 00:22:12 UTC 2022
GCC version: gcc version 9.4.0 (Ubuntu 9.4.0-1ubuntu1~20.04.1)
$ dkms status
nvidia, 515.65.07, 5.4.0-131-generic, x86_64: installed
$ modinfo nvidia | grep ^version
version: 515.65.07
I understand there's a difference between the loaded driver version and the driver version that will be loaded after next reboot, but I would have guessed that the modinfo version would match the cat /proc/... version, or that the dkms version would match the cat /sys/... version, but they don't…
Could someone make a brief summary of what each command is reading?