Does this mean that Google participated?

https://www.gstatic.com/cow.txt

Not just gstatic, youtube.com/cow.txt is also adhering to the standard.

Not a big fan of the canonical cow.

Can’t really see it nicely on mobile

I know robots.txt, I know humans.txt. But I don't get cow.txt after reading the website.

I think it's a bit of a joke and nothing else

It's a chain mail for server admins.

Very amoosing. The cherry on top is that the backend is in Rust.

Rust is insufficiently bovine-themed. The backend should be rewritten in COW language: https://bigzaphod.github.io/COW/

I wonder if Jeff Lawson (bovine) is involved.