I would say it's a step by step work. I have moved my family from Whatsapp to Signal years ago and then to Matrix. I forced them in some way but I just said "sorry if you want to keep contact we will have to find another app, I don't accept Whatsapp ToS." It took some time but my close family and friends are there and I regularly get someone to join, friend or family. It's still close circle but it's also a good thing. Same went with work. Colleagues wanted to do a whatsapp group for a project and I basically said "No, best I can do is Signal." and they went with it.