I struggled with this problem for some time and found a solution or rather the reason it happens. Let me explain and hopefully it will help someone.

My problem manifested itself a little different. With all my usb/serial devices plugged in and powered at the time I booted the pi, all was good, sometimes. If I unplugged/plugged in a device, my dev rules where ignored. They would show up connected to gpiochipN or somewhere in the usb bus. Just as an aside, I also have a PoleMaster that could be started as a regular user under one os kernel, but after an upgraded could only be started as root. Udev rules where a constant source of wasted time and effort.

The breakthrough came after much research, trial, error, and a revelation. The revelation? The kernel version and module versions where not the same. I had a recent kernel with no matching modules directory. Verify with :

uname -r

ls /lib/modules

sudo apt update

sudo apt full-upgrade