I think a lot of this conversation boils down to someone needing to make an ESP32 device that sits in your OBD port and can be addressed directly for those who have a car that can connect to your home WiFi. I feel like one of those already exists…
Fun fact: In the UK there is no ability (DVSA/DVLA[requirement to legally taxing/insuring a car]) for legally driving a converted ICE to Electric car. This is due to the MOT test having a test for CO2 and if the test returns null or “out of bounds” the car fails it’s MOT and therefore is illegal to drive.
FWIW; this is not a practical problem, it’s a political one. Conversion kits don’t get a pass/by from the law, they are subject to the same laws just like home brew conversions.