BunsenLabs (Debian derrivative) won't shut down (Failed to start poweroff.target: Transaction is destructive)

I've been ducking for the solution for a while and finally I've found a solution. It worked for me. I don't know what triggers this weird behaviour though.

This is the recipe for shutting down your Debian:

1. Run ps aux | grep suspend.

2. One of the results should be looking like this

   root 3651 0.0 0.0 8668 1716 ? Ss 07:18 0:00 /lib/systemd/systemd-sleep suspend
   

3. Run sudo kill 3651 or whatever the pid of your result is.

4. At the first time, I was able to shutdown the PC. The second time the PC went to sleep immediately after the kill command.

It is suggested that you log out of the graphical desktop environment before killing the process.

Source: Ubuntu Forums.

I am adding another answer to this question, because in my case there was no systemd-sleep process running, yet I could not halt, shutdown, poweroff, nor reboot my machine. (I think this behaviour is once more proof that systemd fully qualifies as a malware, but let's leave that discussion for another time.)

In the end, I resorted to the kernel for help in my struggle against systemd. The following is not so different from a hard-reboot (pushing the power button), but can help, in case you don't have physical access to the machine:

echo 1 > /proc/sys/kernel/sysrq
echo b > /proc/sysrq-trigger

Once rebooted, proceed by wiping out the spawn of hell.