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That's interesting because it seems perfectly intuitive to me.

Both in terms of understanding the physics (weight of water above the column divided by the area of that column, and then any water around the column just has to have the same pressure to contain that column) and just plain practical experience from e.g. dipping underwater in the ocean and not getting crushed like a bug.

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It is very counterintuitive when you reason in terms of weight though. If you imagine a pile of rocks for instance, it makes sense that the strain on the base of a pyramid is lower than on the base of a column of the same height and base area.

You have to visualize the atmospheric air pressure to reconcile the result with intuition.

I mean it's perfectly intuitive to me that a pyramid of rocks isn't going to collapse, so you don't need a container to hold it in. The closer analogue would be pouring sand in to a tube vs. pouring it in to a bottle that widens below the neck - it's intuitive to me that the bottle would be under enormous strain to hold the sand in. (And, incidentally, the part of the bottle where it widens would be applying extra "weight" to the sand below it)

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