So, fstab says to mount a filesystem, and systemd mounts the filesystem. The reporter explicitly says they want the filesystem mounted at boot time. The response is correct: there's no such thing as "mounted at boot time but not 'after system boot process completed'", because there's no magic "after system boot process completed" point at which that behavior could change. When the device becomes available it gets mounted.
sysvinit and typical distribution init scripts couldn't implement the behavior seemingly desired by the user, either.
The ticket follows the sensible approach: Document it, and close it as expected behaviour, and it did lead eventually to an LVM issue that did require a fix [0].
systemd did good here, above board, but there was a faff about it, because the expected behaviour of the audience differed from the reality of the situation.
