There's 2 billion users on WhatsApp, no ones moving away from it. Just how it is.
I tried to get friends and family to use Telegram (my preference) & Signal, but WhatsApp is literally the #1 app most people want and need. No one's interested in anything else.
Everyone in my family has an iPhone so it's bizarre that no one uses iMessage, but they have their social groups firmly established in WhatsApp and no one's going to migrate away from it.
iMessage would have had a shot at being a proper competitor if it was available on Android from day 1, but it wasn't.