Well, when you post a picture from St. Peter's looking in the direction of one of the few places where there is a gap in the wall surrounding the Vatican, sure, you can make it look like there is not much of a wall.
However, if you look at this map of Vatican City, please note the map key that says "International Boundary (city wall)", and which corresponds to the solid line that encompasses, the entire city except for openings at 3 points, then it does seem like the wall is quite real:
