There are no foods for protozoa, beneficial nematodes or microarthropods that engineer soil pores. In just a few years, what little organic matter was present is used up, and the sand compacts like concrete. To open up the spaces between particles, you need to inoculate the beneficials, and provide food. Soil structure can begin to come back within days as the bacteria and fungi grow. But be careful - too rapid growth of bacteria and even fungi in some cases can suck up all the N, leading to yellow or dying plants.
Balance is critical in the conversion from straight sand to organic matter plus sand.