That would be a good reason to be careful about floats, but it's not the issue described. There's just one implementation for the author's language with just tw

That would be a good reason to be careful about floats, but it's not the issue described. There's just one implementation for the author's language with just two types: some kind of integer and some kind of real called "number". Any choice they make for the latter would have the issue in the article, but wouldn't have the issue you're describing, because there'd be a single nearest value in the chosen representation.