I have been of the personal opinion that email should be end to end encrypted. This would be another reason why. Think about how much personal information is easily exposed by non-encrypted email. It would be like having the 99.9% of the web sites still using http as opposed https. I have seen more than one doctors office have an agreement that they want you to sign so that they can send one unencrypted email. (Most people don't pay much attention to the agreements that they sign and non-technical users likely don't know that their emails can easily be read by several parties.)