That's why End To End Encryption is the best solution we have, which balances usability with good security. It reduces the surface of attack to just the encryption algorithms, their implementation, and the keys, which is substantially easier to audit and doesn't change when the products evolve. It also allows you to say "fuck it, have the data, its encrypted so who cares". Finally, it logically separates the attack surface into two distinct parts; attackers need both the keys and the data to do harm, either alone does nothing.

In practice, trust comes down to "can I protect the keys". That's something I can trust myself to manage well, and plenty of companies sell solutions to make it easy (ex: Apple and the secure enclave of your phone).