When looking at pixel size, we saw that there’s little difference between having a few large pixels and having lots of small ones, once you consider the whole image. This is because sensors have the opportunity to capture the same amount of light per-whole-image, regardless of how many pixels they have.

However, when looking for a new camera, there often is a way of getting more light and therefore better image quality: a larger sensor. This is because, at the same exposure settings, a large sensor is given the same amount of light per unit area, but has a greater sensor area capturing this light.
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https://www.dpreview.com/articles/2708462822/choosing-a-camera-is-a-bigger-sensor-better