Those cars' emissions can also be made worse over time without changing anything about the car simply by changing the fuel used to generate electricity....
Such as Germany currently decommissioning nuclear plants...
That didn't stop Germany from reducing its oil, coal and gas consumption though. Those reduced over time or at least stayed the same while renewables steadily increased.
Source: https://www.cleanenergywire.org/factsheets/germanys-energy-c...