It's infuriating because nobody will consider any other messaging app. My phone's carrier also gives everyone several free GBs of WhatsApp data per month.
Woah. I knew there were still places that charged for or metered SMS use, but I had no idea that the restrictions were that severe.
Funnily enough the volume of scam calls and txt that I receive via WhatsApp is why I have it disabled.
The only reason I ever use it is because we sometimes need cross platform group messaging to organise plans with other families or school groups, then I delete the app again
EDIT: out of curiosity, which country are you in?
Quite shocking, yes. SMS used to be free in the early 90s until the providers figured out that they can charge for it. They priced the 140 byte transmission at 0.20 CHF in Switzerland, and in some plans you still pay 0.20 CHF for 140 bytes over SMS, while you can get unlimited data.
Whatsapp rose because carriers didn't count any whatsapp payload towards your metered bill. Basically, Whatsapp was virtually free-of-charge whereas any other messaging app/system (SMS included) incurs towards your data cap.
At least that's what happened (And still happens) in Mexico.
Meta is surely compensating them in some form
My understanding is the carriers wanted to run these deals because they attract customers who often convert to full internet plans. Messaging is nice, but customers eventually get outside links and want to experience the web or other applications.
Post acquisition, deals moved into Facebook's mobile partner portal, and afaik, there was still no compensation for WhatsApp deals, but the MPP does also offer analytics (audience insights) to carriers, and I'm not sure if it's a requirement to have a special pricing deal to get that or not.
It's been several years, so it's possible the program has changed.
[1] If you've seen that on planes, it wasn't authorized when I was there, and I don't think it's authorized now, but it doesn't stop a motivated network from providing the service.