It isn't phrased as a fallacy, it's phrased as an argument against using a float.
There's obviously some difference of opinion about what "below two decimal points" means. Given that they point out the 0 decimal point Yen, it seems they mean "more precise than", ie more decimal points.
Even if they meant the opposite their own example of the yen disproves that.
Did you misunderstand the statement as being a truthy claim rather than a false claim?