Well La Rambla looks like what we'd call a "pedestrianised street". The parallel roads are open so not much difficulty. Much of the city is litttle square blocks, muchly one ways like NY.
What if it rains. People won't want to walk.
What if you have disabled people who have blue badges? In the Oxford scheme they and many other excepted groups such as carers will be driving around. Some use
diesels, as do HGVs, also permitted. Like Ocado vans.
What if those who are in that tiny victimised group, "ordinary people" want to now what benefit the scheme is supposed to confer, with so many other vehicles buzzing about.? And destroy the cameras...