

It is “built-in” as the name is part of python. However, Python runs top to bottom, rather than having a special entrypoint. So name is just a utility you can use in your design.
While it can be a good practice to define a main entrypoint, that’s more of a design decision and not hard rule. Many applications would not benefit from it because there is only one way to actually call the application to begin with.
Edit: Also not a dumb question. All programming languages have unique elements to them due to how they were envisioned and or developed over time (Pythons 30 years old)
I think that’s context relevant though. If we think about when dates are most frequently used (news, business, planning) it’s typically within the year (or month will give context).
That added with the fact it’s not uncommon in some situations to just provide month/day.
That being said, I don’t think either is better or worse. Just a preference kinda thing, unlike the issue between metric and imperial units.