1. How is this really different to government-mandated microphones and cameras in your house, school, workplace, etc? 2. What’s the endgame here? Open-source encrypted messaging software is widely available. The cat is out of the bag. Every country on Earth could outlaw the technology and it would still be trivially easy for criminals to use it. Do the people behind these proposals not see that?
Trivially easy but probably in practice too much of a bother. I imagine most traffic isn't between well trained members of international terrorist or crime organisations planning major heists, but people who are friends, family members and acquaintances.
They're already using WhatsApp to talk with other friends about every day things so start planning and revealing criminal behaviour accidentally without taking the trouble to move to another platform.