Which government is now a party? All of them? In the entire world? In any case, I don't know how to explain this without getting into a lot of technical detail

Which government is now a party? All of them? In the entire world? In any case, I don't know how to explain this without getting into a lot of technical details, but introducing an extra party who can read everything like that does fundamentally change the nature of the system. If you want a system where data is encrypted such that two independent parties can each decrypt it using only their own secrets, how do you think key exchange, encryption and decryption would work?