First, only an idiot would want a monoculture, particularly in the Linux world, so to those saying "just to systemd full bore or go to (someplace else)" the rest of us need to respond with a very loud and resounding: Fuck You.
That said, things aren't nearly as dire as this post implies. Reading from the responses to the bug he himself linked to, I find the following:
> Unless KDE is prepared to make a statement that it depends on systemd
of course not. Powerdevil recently also gained support for ConsoleKit2, see: http://commits.kde.org/powerde...
Which turns it into a distro problem. Your distribution configured the system in a way that suspend/hibernate is broken. It doesn't come with any of the supported solutions Plasma provides. Which makes it a distro problem. The distro integrates various parts of the software stack. This includes it's the distro's task to ensure that components work together. It failed here by ripping out systemd and replace it with well nothing.
So while I'm sure the systemd zealots would love to see KDE, Gnome3, etc. only work with systemd and drop support for all other distros, this doesn't appear to be happening. In the case of KDE, ConsoleKit2 is supported (and therefor Funtoo, Gentoo, Arch with OpenRC, etc. will continue to work just fine).