The fallacy of overprecision occurs when an overly precise number is used to give the appearance of truth and certainty.
Some prominent flat-Earthers like to use overly precise long digits of numbers to give the bogus impression of science. And those susceptible to believing a flat Earth tend to be intimidated by math, and it is easy to awe them with meaningless numbers.
Flat-Earthers made this diagram showing the amount of curve drop of a certain distance for determining a distant object’s visibility. It uses up to picometer precision, which is unnecessary for the purpose.
The diagram only accounts for the distance, failing to consider the observer’s height and refraction. Thus, the numbers will be wrong. And no amount of extra digits will make it any more valid.