There was nothing inherently low quality about using iron sand anyway. Impurities were carried away by slag and the iron in the sand was easily recovered using washing and later electromagnetism. Imports were used as demand increased.
You are conflating the elemental molecule of iron with the finished product of an alloy of carbonized iron aka as steel.
Yes, there isn’t a molecular difference between the iron found in sand vs the iron found in rock ore. However, the medium in which you harvest your iron and how you’re able to heat that iron, dictates the quality not your final product.
The truth is that the steel made from Iron Sand was not lower quality than the Steel made from other sources of Iron.
That’s not true, no matter how many times you make that unsupported claim.