Yes. ISO chooses year-month-day, which puts largest component first and smallest last. This has the nice benefit that treating it as a string and doing alphanumerical sort matches the actual day sort. Ref. https://en.wikipedia.org/wiki/ISO_8601

The main benefit of Y-M-D, is that no-one uses Y-D-M, and the 'Y' component is easily recognisable. So if you use Y-M-D, then everyone knows it's Y-M-D and there is no ambiguity.

I found out recently the x509/tls certa are YYMMDD

200122

For example. Amazing.

There are benefits to both little endian and big endian

Yes, but the US uses middle endian.

My two favourite date formats are: (1) yyyy-MMM-dd and (2): yyyyMMdd.

Why?

(1) eliminates any ambiguity regarding interpretation. You can have an instance of a server of an unknown provenience and/or regional settings and still count on yyyy-MMM-dd to be correctly recognized.

(2) on the other hand has a nice feature of being sortable and can also be stored as an integer value if needed.

The US standard of MM/dd/yyyy is ridiculous. But it's just one of many and I'm not going to fix the world ;)

On the main topic: if anyone needs to calculate the circumference of the Universe (radius: 50bn lightyears ish) with the accuracy of the Planck distance (approximately 1.6 x 10^-30 meters), they need less than 65 digits of Pi to do so. So, as already stated, it's just a PR stunt, nothing more.

yyyy-MM-dd is sortable (2019-03-14)

yyyy-MMM-dd is not (2019-MAR-14)