Can’t speak for the most modern ones which I know are worse, but I was pretty surprised when I recently got a smart plug with power monitoring recently to find that my system with a 3080 (though, undervolted slightly), 16-core cpu, way too many peripherals, eight various drives, several small screens and dual monitors, only pulls 600-650W under full load.
I got the plugs to help me choose an appropriate UPS, and I don’t need one as powerful as I’d thought I would.
I run Linux on an old gaming PC that I use as a file server / jellyfin server / homeassistant / probably a bunch more I’m forgetting, and that one rarely goes above 50W, lol. Haven’t tested it under full load, though.