Taken to the extreme, if you made such a dense network of roads that it was effectively just one giant paved surface, then I think it's obvious that it'd be inefficient since everyone is barging through trying to go in their own straight line and getting in each other's way. In that case, adding barriers and one-way lanes would intuitively speed up people's journeys. So perhaps Braess's paradox is only unintuitive for simple cases that are very close to our existing road networks.