In typography, this is called an overshoot.

In typeface design, the overshoot of a round or pointed letter (like O or A) is the degree to which it extends higher or lower than a comparably sized "flat" letter (like X or H), to achieve an optical effect of being the same size; it compensates for inaccuracies in human visual perception.

Yes, it makes a difference. Human visual perception is not always a mathematical constant.

In typography, this is called an overshoot. And has been a very long-standing practice.

In typeface design, the overshoot of a round or pointed letter (like O or A) is the degree to which it extends higher or lower than a comparably sized "flat" letter (like X or H), to achieve an optical effect of being the same size; it compensates for inaccuracies in human visual perception.

Yes, it makes a difference. Human visual perception is not always a mathematical constant.