Quality of focus also affects file byte size....

If you mount your camera to a tripod and set manual functions, aperture, shutter, ISO all to the same settings and set the focal distance point to be identical and shoot four shots of the same subject (NO CHANGE) at the settings chosen, you can get four different file storage sizes, whether Jpeg or RAW. This is also true on my DSLR that saves TIFF.

Change the focus for each shot, manually.. For the test do not use AF.

The image that will be the smallest byte size will be the image in best focus.

Taking one image in focus and purposely defocusing the other three will add bytes to the out of focus images. The image in best focus will always be the smallest file byte size.

I discovered this some years ago and often use the smallest file size as the best predictor of best focus.

Naturally, to make this a controlled test, testing relies on keeping the settings, subject content and exposure the same.

There is much confusion, and rightfully so, until the factors that control pixel count, pixel size, byte size and other components that control size are fully understood.

Some need to be understood and others are simply "mental masturbation"

Perhaps like file size related to accuracy of focus. Who Knows?

BY THE WAY my camera that writes jpeg, RAW and TIFF, creates TIFF as the largest byte size file... by a large margin over RAW. It's an Olympus DSLR. I have also used FUJIFILM DSLRS that create all three formats and TIFF is always considerably larger than RAW.

A pixel defines an area of the sensor and ultimately to a corresponding area on the viewing screen or print, not the color value of the area. The light and color information recorded for that "pixel" unit of the sensor can be as simple as on/off (black and white) or as detailed a color and intensity value as the sensor is capable of recording. This capability is referred to as "bit depth," referring to how many bits it takes to store the information for each "pixel" of the sensor.

From there it becomes pure math. Currently a a byte of storage space is comprised of eight bits. So a 10mg pixel sensor recording an RGB 8-bit depth would be: 10mg sensor x 1 byte (8-bit depth) x 3 (RGB) equals a 30 megabyte file before compression and the addition of the file header information.

Larger sensor sizes and higher bit depths just make the final storage requirements larger. Thank goodness for the skillful people who write the lossless file compression algorithms!