Space is also confusing! Then it looks like two separate numbers.

Underscore (_) is already used as a decimal separator in programming languages and Mathematics should just adopt it, IMO.

A competing format to simplify things?

Comprehensible?

https://ijmacd.github.io/rfc3339-iso8601/

I said date. Not time, not timestamp, not period, not week, not range, not ordinal date.

Just date.

You mean thousands separator, yes? Agreed, it’s annoying when languages don’t have this feature.

Ah yes, thousands separator.

A thin non-breaking space also clears up the confusion without the visual clutter of the underscore. It's just inconvenient to use

The problem is our primitive text representation online. The formatting should be localized but there’s not a number type I can easily insert inline in a text box.

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