Even moving the combustion byproducts from where the people are to where the power plants are is a small win. That the plants can more easily install scrubbers for some pollutants is a further small win. That they are more efficient (even with 15% charging losses) is another small win. That the use of renewables can grow over time without car owners having to upgrade is another small win.

Stack up enough small wins and you can get to sizeable gains.