From what I have read, it is better to keep an old IC vehicle as long as you can, before trading it in for an EV, due to the large and unavoidable carbon footprint of manufacturing a new vehicle, of any type. But your next purchase, whenever it is necessary, should be an EV. The longer you can leave it , the greener the EV will be , since the renewable proportion of the electricity it consumes will grow as the years pass. Also the charging network will get better over time. I'm currently running a 19yr old petrol VW Golf, (the 1.4l one with both supercharger and turbocharger, which performs like a 2l but with much better fuel economy). It still works fine and does what I need it to do, so I intend to hang onto it for another year at least.