Yes, very useful for subtle distinctions like this!

Yes, it’s metonymy, as people have said. You also get it in similar contexts where people will name a building such as ‘the White House’ or ‘[10] Downing Street’ to refer to the governments of the US or the UK.

Any MBA?

/s indeed, but you did remind me of a cool image, above: the Earth (and the Moon) not only from space, but from the orbit of Mars!

And, below, the Earth as seen from Mars’ surface:

It’s the the tiny white dot, just left and up from centre.

Not a contemporary one, but during the French Revolution, they used ‘Citizen’ for everyone.