Yes, I've had to disable that systemd feature too; however, in this case it's because I usually deploy a much more application-specific watchdog process. systemd's built-in watchdog might be inadequate or non-portable, but it is not a radical departure from legacy behavior and it is better than not having any watchdog code at all.
Obviously every system based on rc-scripts has been able to run such a daemon for decades prior to systemd's existence. The page at the link you provided even has a link to such a daemon that is at least 14 years old. I recently had an unsolicited email conversation with one of that daemon's maintainers about their plans to extend the daemon to do more invasive application-specific aliveness checking (I thought the idea wasn't insane, but I probably wouldn't use it because watchdog daemons are trivial to implement while solutions to political problems arising from software integration in critical code paths are not).
The more complicated the shutdown code is, the more likely it is to fail. If we try to stop mostly-stateless server daemons (like BIND) which are explicitly designed for and respond well to a famous widely-deployed 20-year-old system-wide SIGTERM/pause/SIGKILL sequence using anything with more failure modes than exactly that sequence, then embarrassing failure is simply inevitable.
Less is better. systemd has lots of tactical cleverness in its implementation, but at the same time it gets the basic strategy wrong.
I have a test machine running systemd. On February 13, 2013 I executed the 'reboot' command and today I'm still waiting for it to finish. Interestingly, the rest of this particular system's function seems to be unimpaired--including systemctl and systemd services--and I still push software to it for testing regularly. I'm now tempted to take bets on how many years it will take for that machine to reboot. It happens to have two independent battery-backed power supplies... };->
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