Well WE know that, sure

How many concurrent users and what hardware if i may ask?

Do you realistically think that’s gonna work?

I’ve no proof of this, but technically the whatsapp app is closed source so they could push an update that collects the private keys, if they don’t do this already

Yes, however do you remember the big fuss over 5g tower tech coming from Huawei and how that is a security issue? Well turns out the 5g towers can employ beam forming for better connection with each phone. And the interesting thing is that AESA radars work much the same - so you can imagine what a nation wide network of these towers would provide for china in terms of air traffic information