I’m happy to hate systemd for just about any reason, but is this bug special in some way? There’s not enough context here for me to determine if this is proof that systemd is irrevocably broken.
It might explain a few things, bash history lost, ungraceful Firefox shutdown as mentioned in the comments, but I don’t think this is anything that can’t be fixed, one comment mentioned using a timeout, the default should have been one and a half minutes apparently.
Comment #9 seems to hint at some frustration with upstream…
Note also that despite the bleedingly-rapid development its proponents generally seem so proud of, the bug remains unresolved at nine months of age. Not exactly a quick turnaround for a project that seems eager to use every latest-greatest non-portable API as soon as it exists (or in the kdbus case, before it even really exists).
I guess it reinforces perception of the ‘move fast and break things’-attitude of systemd et al. Not necessarily as a proof that systemd if fundamentally wrong.