I think the challenge is keeping it up for years. And issues like you thinking that the mail is sent, only to learn later that a spam filter ate it somewhere. N

I think the challenge is keeping it up for years. And issues like you thinking that the mail is sent, only to learn later that a spam filter ate it somewhere. Now you have to think: what else is being eaten? For how long? What if you do need to send the email right now because of a deadline or similar? So currently it's not infeasible, just an uphill battle.