> the current generation of electronic vehicles are a terrible idea... Although perhaps a mere half is not what people would think at first when they just compare tailpipe emissions

The methodolody used by IEA for that chart uses the 2021 global average grid carbon intensity to calculate its electricity generation. If you live in Iceland, Sweeden, UK, Vermont, or similar regions with highly decarbonised grids, the majority of the chart's Electricity co2e isn't generated for that vehicle.

You've got to consider your local average grid carbon intensity, and how that will change across the 20 year lifecycle of the vehicle.