> Leading zeros aren't a thing for a reason.

If they aren't a thing, why are we talking about them? Clearly they're a thing. And not even an obscure thing. If you've ever used commonly used representations like ZIP codes, bank account numbers, or serial numbers you'll no doubt have encountered it before. And that even goes for dates. ISO 8601, for example, requires leading zeros, including for the year component. "1" is not considered a valid year under that standard. It must be represented as "0001". Granted, ISO 8601 only requires a minimum of four characters to represent the year, but expecting at least five characters is conceptually just as valid.