Well, I’ve followed that approach during several years, because I really don’t like having WhatsApp installed (or any Meta app for that matter), and all I got was be disconnected from society. Most social groups or organizations use WhatsApp as a gathering/coordinating tool. Of course, at a personal level people can always phone, but for some reason, I don’t get many phone calls, if any.
You could say “time to make new friends”, but again, it’s pretty widespread the use of WhatsApp for everyone here in south Europe. If you’re not there, you’re out of most social circles.
I’m going to install Telegram, but I’ll probably install WhatsApp again once the damn usernames are operative (why is it taking them so long??).
But having the ability to communicate with everyone, app-agnostic, using my preferred one (iMessage) would really be a blessing.