I'm in the process of getting my Home Assistant environment up and running, and decided to run a test: it turns out that my gaming PC (custom 5800X3D/7900XTX build) uses more power just sitting idle, than both of my storage freezers combined.
Background: In addition to some other things, I bought two "Eightree" brand Zigbee-compatible plugs to see how they fare. One is monitoring the power usage of both freezers on a power strip (don't worry, it's a heavy duty strip meant for this), and the other is measuring the usage of my entire desktop setup (including monitors and the HA server itself, a Lenovo M710q).
After monitoring these for a couple days, I decided that I will shut off my PC unless I'm actively using it. It's not a server, but it does have WOL capability, so if I absolutely need to get into it remotely, it won't be an issue.
Pretty fascinating stuff, and now my wife is completely on board as well; she wants to put a plug on her iMac to see what it draws, as she uses it to hold her cross-stitch files and other things.
Yeah I made a similar discovery after installing a Shelly Switch with Power Metering. The monitors and their brightness make a huge difference as well when in or near idle (for photography, so not a surprise). I've also implemented an "anti-standby" function, so the switch opens whenever the current falls under a specific threshold.
For the WoL, since I have a switch, I configured my BIOS so it would turn on after power loss. Now I can start to boot up from afar :)
That's certainly one way to do it...