Having a massive car free zone is a huge obstacle and forces them to take public transit to the city centre. That is of cause part of the plan, but when you are from outside the ring, it is going to increase travel times. Just to be clear I support the idea, but this is a case of not being able to make an omelette without breaking some eggs.

Also the proposal is not going to happen anyway. Right now it would be about smaller changes, like removing parking and closing some streets, rather then a massive part of the city.