Thanks to this tip, I was able to finally resolve my issue of KDE screensavers not automatically starting, or working with the hotkey enabled.

It makes perfect sense in hindsight.

The solution is to simply enable “Power saving features” from the Control Center in KDE.

To enable a “hotkey”, you can click “Advanced” for a particular screensaver (ie: Electric Sheep), and specify which corner you want to activate the screen saver.

Update: It appears that when using with a KVM switch that the resolution is not saved after KDE does a “power down” of the monitor. A bummer since I do not have a solution at this time.