The barrier for me to go EV as a private buyer is the initial cost of the car.
Same with us. But in any case, our Fiat 500 is only 5 years old and has got a good 10 to 15 years more life in it, probably more, before it would need changing.
The 'greenest' strategy, if one already owns a reasonably recent ICE vehicle, is to hang on to it but reduce one's use of it wherever possible, ideally switching to a bicycle or e-bike for short trips into town and suchlike.
