Comment by andrewl-hn

A lot of SMBs use Instagram to connect to their clients, so Instagram build-in messenger is a default option for a lot of people (especially women) in many parts of the world.

Some places have regional messengers that are very entrenched, like Line in Japan or KakaoTalk in Korea.

WhatsApp is a default option in a large number of countries including most of Middle East, parts of Europe, Brazil, most of Africa, Southern Asia. To me it is surprising, too, because out of all messaging options WhatsApp seems like the least developed and least ergonomic.

And yes, this does mean that most people share whatever data Big Tech wants. They use Meta to talk to each other, auto-upload their photos to Google, click "accept" to every cookie banner so that thousands of no-name companies around the world know where they are and what they are doing at all times.