Btw. there's no "lack of WhatsApp on Firefox OS phones". I'm using OpenWapp on Firefox OS day by day. And it's working. Another WhatsApp client is ConnectA2 (which I didn't use by now)
Unless of course they invent their own WhatsApp, as many other regions have done. I mean, WeChat anyone? Chinese people refuse to use anything but that.
If you ask me, in five years another messaging service will be up-to-date. But you may be right, the internet at all is getting multi cultural. That will be really interesting times.