By sending emails from a unique random email address, we trigger a number of UX issues:
1. It's not great receiving mail from a different email with each message. I can't white-list or filter it easily. E.g. if it falls into spam
2. Mail clients remember the email address and may suggest it when typing the name.
Proposal: it would be better if we sent emails 'From' a consistent mail account, but used the ReplyTo header to ensure responses get sent to the unique account.