Pixel 5 is "small" in android parlance, but still bigger than the Pixel 4a for instance, which is already slightly bigger than the SE.
I think parent could have been fine with a Pixel 4a if it wasn't for it starting to age (using the lastest OS on it, feels definitely slower at times , especially when starting the camera which is a bummer)
It's the only phone that tore me away from the iPhone 7/8 SE form.
The fingerprint sensor is arguable in a better position (on the back).
Plus you get better battery, an OLED screen, 90hz.
It sucks the Pixel 6 series went huge and bulky instead of continuing the successive wins of Pixel 3,4,5.