Previously discussed here: https://news.ycombinator.com/item?id=15340729

As an engineer, I appreciate the depth of this post. However, I'd also appreciate a more approachable version that I could share with a broader audience. E.g., without understanding anything about hashing, SGX, etc., how can we best explain the advantages of this approach over the "upload your contacts list" request that you encounter in other chat apps?