Also naturally sortable if represented as YYYYMMDD, unlike default guids (unless specifically using sequential guid generator)

Being pedantic here, and somewhat off topic.

In general, a "date" (assuming you mean year, month and day) is not universally unique unless you provide the calendar system under which it occurred.

See: https://en.wikipedia.org/wiki/Dual_dating

This probably doesn't matter much going forward, but it does matter when addressing historical dates.