At https://www.livescience.com/archaeology/ancient-egyptians/sphinx-may-have-been-built-from-a-natural-rock-feature-eroded-by-wind-study-claims … It is possible that wind erosion made a rock feaure in Egypt resemble a lion laying down is the basic premise. Asuming somebody saw the possibility of fine tuning the feature to what we know today. Something like that may account for the erosion of the sphinx as heavy rain as an erosion agent appears out of the question. The problem is that the erosion seems to date much older than the sphinx from a historical point of view, carved in around 2500BC – or thereabouts. Did the erosion create the idea in the mind of somebody in Egypt? An interesting idea. It is certainly a way around the difficulty of the geology disagreeing with the archaeology. The idea, I suppose, is to put the counter view to silence.
Researchers simulated wind erosion, assuming it took place over thousands of years, and suggested that harder parts of the rock formation could account for the head. Back in the 1930s research suggested the sphinx was composed of two formations – not a single one. One for the body of the lion and the other accommodating the head and chest. It was a theory that was never accepted – in public, at least. In private, may be.