No, you can play the game as a “nomad” and have plenty of success.
Every Prospectors citizen has there own free central storage located on the same plot as the future railway. All Prospectors citizens will have their 12 cells in Central Storage (plot -01/-01) and will be able to store own items there. This makes this new feature an amazing upgrade for “nomads” (players who don’t have a plot rented) because once the central storage is constructed, you won’t need to rent a plot just for storing your stuff anymore. All citizens will now have access to storage in the central part of the map, which also provides an advantage for transportation logistics. The primary function of these cells is to provide citizens with storage for items to be transported on the train to the other Prospectors Land.