1) Don't let perfect be the enemy of good
2) For the record EV use 99% regenerative braking so at least that source is practically zero
3) Decoupling CO2 emissions from the car means you can upgrade your power grid to be greener without having to replace all the cars already circulating. It's an enormous advantage which should be given due consideration. Also, it's easier to manage the emission of all the CO2 in one place, and mandate better filters/capture systems there, than just spew it out of every individual exhaust pipe, where many capture systems are not feasible due to cost, size or other consideration.
But, most importantly, let me repeat:
Really, really, don't let perfect be the enemy of good, please.