I salute everyone here who is able to switch away from WhatsApp. I wish I could dump it as well, but I can't.
Why? I volunteer with a group where one of our main things is to have a small army of people out doing coordinated-but-physically-separated tasks. Everyone has a smartphone of some kind but they're of varying types and quality. We tried using group SMS but that was a disaster, as group-SMS is bad enough but group-SMS-with-30-people is one level below "just fax everybody."
WhatsApp, meanwhile, lets us make daily groups, have a QR code that volunteers can scan at check in to join the day's group, app versions that work on the shittiest Android phone all the way up to the brand newest iPhone. And as a bonus, since almost all of our volunteers have friends and family outside the US, pretty much everybody already has Whatsapp installed and knows how to use it.
The one time our Executive Director tried switching apps, I had to spend an hour talking him out of WeChat, of all things. Point being, we need individual action to pressure our friends and family groups along with regulatory action so that massive platforms can't abuse us like this.