Comment by arter45

Yes, you can have two messaging apps, but people will have a “main app” which is typically the one used by important people in their life (family, partner,…) and/or the one used by most people. Meanwhile, if you all use two apps, everytime you want to check up on a friend you have to check two apps.

Imagine all your friends love pizza, as do you. Suddenly you decide sushi is better so, naturally, you tell your friends to try out sushi at the next dinner. Assuming some of your friends are not absolutely against sushi, yes, you’ll have that sushi dinner. But what if they don’t like it that much? They will revert to pizza or accept sushi, occasionally, when they want to see you, while still prefering pizza for all other interactions.

There has to be a perceived advantage for changing habits. If few people see the benefits of Signal or other non-Whatsapp apps, they will not change their minds.