Deleting WhatsApp though would be very difficult. It's completely replaced SMS as the primary means of communication for every personal network I am part of.
Would people just not bother replying to you if you sent them a message over SMS or Signal?
Person to person. Probably Yes. But it's the group chats in WhatsApp that are the main sticky point.
Yeah, don't think I can move off Whatsapp. It's the default communication channel for me. Virtually every conversation happens on it, from planning an evening out to asking my wife to pick up some eggs and milk.
Same, but then again I'm only part of 3 groups and I'm hardly ever available to talk on it. I just call back almost every time.
Yes, it's enormously frustrating and it's practically impossible to get anyone to move off it.