I suspect that they all are. One usedc to be able to walk from the ship to the port entrance and then grab a taxi to the train station, but on my last visit there were "No Walking" signs everywhere and even a patrol guy that turned us back to the ship. Celebrity charged $5 each direction for the transfer. I am not sure if Princess will do the same or not.
It is still worth it though, as the train is so much faster than a moto coach to Florence and then when you are there, a driver is useless.