Tire rubber accounts for about 25-30% of all microplastic emmission on land. But we are talking about Q-tips and putting filters into washing machines, because the car lobby successfully stirred the discourse away from themselves.
Pretty much. The tire abrasion is dependant on the weight and the speed of the vehicle. So unless your e-bike weighs multiple tons and reaches speeds of >100km/h, it will be much better than a car.
Kinda, yeah, that would help. A Ford Model T had 540-750kg weight, and a top speed of 67km/h. That's significantly lower than modern cars.
But a Ford Model A from 1928 already had 954-1144kg and was able to reach 104km/h, which is not too far off from the regular operating values of a small modern car.
If you'd use modern materials and engines, it wouldn't be hard to make a 500kg empty mass car with a top speed of 50-70km/h that fits 5 people, uses hardly any energy to move it and has very little tire abrasion.
If there were no heavy and dangerous cars around that you need to be protected from, something like an electric autorickshaw would be a perfectly adequate city vehicle.