Being a refusnik is not difficult.
I don't have WhatsApp. I do have Signal.
Most of my family now have Signal. Those that don't can text me. Or ring.
Signal works fine on an e foundation phone. Firefox/Signal/Mail Client. That's all I need.
From the conversations I've had about privacy with friends - the general impression I get is that we like to talk about privacy and it's importance, but we are, in fact, prepared to do nothing about it. They'll keep their Facebook stuff (we can all find a reason why we "need" to). This won't change anything, but they're OK with that.