[hunter2_]

Good point. Are there any use cases for E2E when the server isn't potentially adversarial to any clients?

Separately: affordable servers likely are accessible to infrastructure providers (whether a VPS, or bare metal at a colo, etc.) so it's tough to say that "my own server" is usable exclusively by me and therefore not adversarial. Plus, maybe people want to use my server and consider me adversarial for whatever reason; they should use their own server instead, but might not have the skills.