OK, that’s interesting.
Yes, that seems likely: systemd calls udevadm settle, which times out. I don’t think that is usually much of a problem, but still, could point us in the right direction.
You can poke around the logs of the last boot (journalctl -b for the entire thing, or journalctl -b -u systemd-udev-settle -u systemd-udevd for just the udev-related stuff) to try and see if it is your card that is causing the holdup.
Also, you could override systemd-udev-settle to run udevadm settle with the --debug-flag to get more output.