It absolutely isn’t a global thing. Many Europeans get confused when they first encounter it from a brit or american for the first time. My indian friend lived in the US for a year and never got used to it, would still occasionally accidentally answer for real.

Then there’s places where there’s a set, expected answer.

Like Ireland:

Alright?

Alright.

France:

Ça va?

Ça va (bien).

That’s just my experience!