Assuming that you have your email configured to require TLS on the receiver than I don't see what is wrong with email. Even if they downloaded the files from yo

Assuming that you have your email configured to require TLS on the receiver than I don't see what is wrong with email. Even if they downloaded the files from your server they probably just stuck them on some file share which at best is just as secure as their email inbox was. Many organizations have policies for email retention and similar that is less likely to be enabled for file storage. I would love to see more places just use email. Instead I get these messages with links to proprietary services to get the file. Now I need to download and store it out-of-line with my conversation. I think the major issue with email is that encryption is optional with transparent downgrading. You can imagine that if it supported something like mailtos:me@example then it could be used as a secure medium, much like https can be trusted today.