I love when the journalists try and generalize the headline on a study like this by saying "EV may produce more CO2 than gas". And isn't it ironic that ICE drivers looking for holes never seem to call in to question their own grid use and the cleanliness thereof. But if I'm going to drive to work using electricity, than somehow suddenly it must be cleaner than their ICE or I somehow become an agent for climate destruction. And they can spew all the particulates and toxins they like, because they (conveniently) only want to talk CO2 now.
We all need to stick to the point. The point is not whether an EV MAY pollute more; the point is that the EV CAN pollute less. Your ICE CANNOT pollute less (except for minor fractional improvements over time). Now that we've got the car done, let's work harder on the grid.