Ah okay. I sort-of suspected that that was the case. And I see now that enabling server mode silently turns on the shared memory option.
It's fine, I guess. I mainly needed that option because there is no "start logging at startup" option, logging has to be toggled on manually and will not...
I checked https://www.hwinfo.com/add-ons/ and found these oddities:
GenericLogViewer - download link redirects to hwinfo's main download page.
Remote Sensor Monitor - download link redirects to hwinfo's main download page.
LCD Smartie plug-in - download link points to nonexistent forum url.
I have a malfunctioning pc so I decided to remotely record its voltages and temperatures via HWiNFO. Exactly 12 hours and 5 seconds in, my logging instance popped up a notice saying that shared memory is limited to 12 hours. The remote sensors got greyed out and now it's just logging the same...