I want to dip my toes into the smart home world and decided that I want to use homeassistant and primarily use devices based on zigbee, as I do not want to overload my wifi with a bunch of devices.

Smart plugs seem to be most interesting to me as I would like to have accurate power measurements for my homelab and applicances. The keyword is accurate here. There seems to be some science showing that the accuracy of smart plugs can vary a lot. I have read that devices that are flashed with the tasmota firmware can actually be calibrated. Unfortunately this firmware is only available for wifi devices.

So my questions are:

• Are there zigbee smartplugs that are known to be very accurate or can be calibrated to be very accurated?
• Is preferring zigbee over wifi actually a good Idea? I mean both use 2.4 GHz, which is known to be crowded. When will wifi smart home devices become a problem?
• Is a calibrated tasmota smart plug more accurated than a typical zigbee plug?
• Is this inaccuracy reported in the paper even relevant for non-scientific use?