> Truly secure systems don’t require trust.
This is a chat app so, by definition, security requires trusting at least one other person. Also, I think experience shows that secrets can often be least trusted to those who have some interest in/use for them, with the secret owner often being the least trustworthy of all. So I'd say that if you trust yourself you're already probably trusting one of the weakest links in whatever chain of trust you would have.
But seriously, pretty much every secure system requires trust, and the more it relies on technology, the more trust is required. You need to trust there are no backdoors or holes in a long chain of hardware and software that no one person can possibly verify, and if they hypothetically could, they could only hypothetically do so with the help of verification software that they could not themselves verify, at least not without dedicating a lifetime to that goal. Trustless security does not exist, and attempting to achieve it by adding more technological layers and more complexity reduces rather than enhanced security. We should make it easy for us to choose whom to trust, not work on a futile attempt to take trust out of the system.