The carbon won’t be captured as in buried, it’ll be burned for energy of some form and the CO2 released into the atmosphere. And at the same time, it will keep the mines open and busy pulling new carbon up out of the ground, when otherwise the economics would probably dictate reducing overall production. Meanwhile a battery electric vehicle can charge from zero-CO2 power without wasting a ton of it on electrolysis (which isn’t available at scale yet anyway.)