Weird that this is your association as using it would require an iPhone which most youth don't have. My thought was Telegram, which is omnipresent at least around me, with Whatsapp often being kept just for the parents or older relatives.
No, it's used by just about everyone. Generally the younger the person and the bigger their city, the more likely they are to gravitate towards Telegram rather than Whatsapp.
I know, and it's terrible that it's so unavoidable. I managed to avoid Whatsapp, but without Telegram managing university life would be incredibly hard.