I’m here to report that there is a lot of bad academic literature on life cycle analysis of carbon emissions from different drivetrain-types.

And by bad, I mean narrowly good—as in yes I can see why that got published—but it literally contributes 0 to reasonably assessing prospective carbon dioxide impacts of different technologies.

A few things (non-inclusive) that stand out:
Let’s just pretend that we entirely throw the battery away after an arbitrary number of miles;
Oh, and no change in the carbon dioxide intensity of electric power production over 15 years: seems fair.

More subtly, at this point every million electric vehicle that we incrementally produce reduces the energy intensity of producing the next million electric vehicles by 4%.

For internal combustion engines that energy intensity reduction is 0.01%.

You have one massively mature technology that literally depends upon burning carbon-based fuels to move you around and another still very early technology that allows you to generate the energy elsewhere as efficiently as possible.

And people are like: it’s a close race!