This is just the sense of touch, used in a certain way ... people are detecting resistance in the sand as it pushes against the object.

Yep.

"Remote touch allows the detection of objects buried under granular materials through subtle mechanical cues transmitted through the medium."

IOW, it's not a "7th sense" ... that's absurd clickbait.

This is exactly how tradesmen and craftsmen use their hands. I guess they don’t teach this at university :D

as a maker/tool user, I can vouch for that, but it goes much further,and as an improvisational guitar player and singer, digging in and flat out going for it, generates tones and resonance that cant be done cold. There are many simple demonstrations and tests to show this useing found objects.