There is rather an easy solution.
For the more Management-oriented, you could even think of it as a SMART (Specific Measurable Achievable Realistic Timely) solution, i.e. the holy grail of targets.
We, the technical community, should agree to adapt our products to suit a solution they provide, within one month of it being found to meet criteria we will set.
To start with:
* It must be possible to decrypt the data in a timely fashion (i.e. without brute-forcing it) at a properly warranted request of a Government agency.
* End-to-end encryption must remain possible
* It can be proven that it is impossible to copy or otherwise disseminate the data once decrypted
* Warrants can be proven to be legal in both the localities where they were created and where they are effected
* Warrants applied to the data can be audited
* Data outwith the warrant should be utterly impossible to decrypt without obtaining a further warrant
* Foreign governments should be able to decrypt the data with a common warrant structure.
* The breadth and rate of warrants should be limited for a certain dataset to prevent the government simply warranting all of it everywhere and decrypting the lot
* It must be possible to highlight when data has been decrypted/viewed and what data was encrypted/viewed
* All of the above must be part of the encryption algorithm itself; these controls cannot be baked into an application, they have to be part of the mathematical theorem that forms the basis of the encryption algorithm, and any removal of these safeguards should change the output so that there can be no other method of decryption
* It must not bias towards one country or region
* It must not rely on stored (or even known) keys
* It must not work any slower than current algorithms
* It must be implemented so that if it is ever broken the people pushing for it at the moment (individuals as well as agencies) are imprisoned and/or face execution (depending on jurisdictional maximum sentences).
* Research efforts towards this must be funded lavishly
And some representatives of the tech industry should be held to this in a court of law. And shortly after unicorn/pig hybrids fly over a frozen Hell the security services figure out how to meet these criteria and we can start worrying about how to implement it.