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Stupid question, what stops us from doing visible-light binoculars with 1x zoom but an aperture larger than human eye pupil?

I know that regular magnifying binoculars can boost the magnitude for stargazing but is the magnification part necessary?

Edit: Apparently this law does: https://en.wikipedia.org/wiki/Etendue#Brightness_theorem

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You can have light boosting binoculars with 1x zoom. Similarly, looking through the viewfinder of an SLR camera will show the light- gathering capability of the lens. The very best light gathering camera lenses (and binoculars) only collect 2 to 4 times more light for a given focal length compared to the human eye. Since our vision is so nonlinear in sensitivity, the 2-4x boost doesn't seem like much. The brightness theorem only says you can't "perceive an object to be brighter than it is at its surface" (my interpretation)

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