Impossible. Everybody I know uses WhatsApp.
Gonna imagine most of the responses will be from North America where WhatsApp use is significantly less.
Being based in Euopre, I’d say probably no; everybody uses WhatsApp. We used it a lot before Facebook bought it as well.
Finland. Wa is rare in business use of any sort. My employer bans it for anything work related as do many others. I’ve seen maybe one hands fingers worth of businesses with a wa front.
Various associations and clubs do use it for group chats, though.
Also, absolutely not. And you should never trust anyone who says anything like “in Europe” or “Europeans”. It’s a continent of dozens of countries and cultures many of which have been in war on and off for centuries. There is absolutely nothing that is uniform across all of Europe.
In many countries cheap/unlimited SMS was not a thing decades ago, so whatsapp filled that gap. Nowadays things got way better, but people are already used Whatsapp, and in some places companies even offer “unlimited whatsapp” in their plans, so seems unlikely to change.
Also in smaller countries whatsapp and viber were the way to communicate with friends and family in other countries. Not only messages, but audio and video calls. Audio messages are also quite important.
And groups, that’s another vector how Viber spread around, parents got to have groups with other parents from their kid’s school class.
I usually ask of people have telegram and I’ll use that with them instead if they do.