I'd love to know the demographic breakdown there. For instance I know students in some relatively isolated corners of the world are still, ubiquitously, using it to cheat. And a quick search gives around 1.4 billion students globally.

Obviously it's not just students, but the fact it [numerically] could be is rather amusing and makes me surprised that it's only 1 billion active users, since GPT has a lock on name recognition amongst low information users.