if you zoom-in on a line you draw, would it be possible to zoom-it infinitely and thus attribute a length of infinite digits, or would you not be able to go after a certain point and all you would see of the line would be tiny particles arranged in a discrete manner, which you could then use to determine the length of the line in cm? (let's say you know the line you drew has at least 1 cm but it's lower than 1.2 cm, you would count how many elementary particles there are in 1 cm, then count exactly how many elementary particles there are left on the line, and then convert the number of particles you counted to the equivalent in cm, thus getting the true, precise, exact length of the line your drew)

If it's the latter, doesn't it disprove the existence of real numbers in physical reality?