It would encourage terrible levels of self-indulgence. Imagine:
* "It costs nothing so I air-condition the entire town."
* "It costs nothing so I have my smart car follow me around 24x7, in case I want it."
If electricity was actually free and unlimited - all that energy goes into heat. We're worried about warming from CO2, imagine the energy output from everybodies every whim!
Accelerate global warming as everyone embarks on the crypto mining business.
It would incentivize people to use electricity freely, which in turn accelerates the pace that we burn fossil/legacy fuels.