As I already mentioned, I already do not use Whatsapp. That is a massive sacrifice where I am. You may not be aware of this (I'm guessing American), but in western Europe almost everybody is now using Whatsapp for pretty much everything. Businesses are replacing the phone and email with it. The situation is even worse in Latin America.
If you meet a new social contact and you don't have Whatsapp, that's likely it, you will not be keeping in contact with that person. Typically they have Telegram installed but hardly use it (so the app gets killed and they won't be notified of your message). As for Signal and the rest, most people haven't even heard of them. I speak from experience. It's a disaster and I worry the people who populate this forum (i.e. Americans who still use SMS) are not familiar with how dire the situation now is elsewhere in the world.