"Electric-powered vehicles, of course, have no exhaust emissions. However, because they’re 24 percent heavier on average, the study found that EVs shed more particulate matter from tires and brakes, and also kick up more particulate matter from road surfaces."
If the brake pads are smaller and aren't required to slow down in many cases, the EV should win, especially when the average EV on the street is likely similar in weight compared to an average non-EV vehicle.
As far as kicking up existing particulate matter, EV's shouldn't be penalized for kicking up dust on the road which came from others cars, which are almost entirely non-EV cars and 18-wheelers.
I bet there are other more significant factors to derive impact on pollution from EVs than brake dust, such as the source of electricity used to charge them.
I'll try to look at the study later to see how the 1% difference between road pollution between gas and EV vehicles was calculated.