Ask HN: How to handle persistent mis-delivered emails?

I am fortunate enough to have the gmail address that is {given_name_initial}{surname}@gmail.com. However, I am not the only person in the world with this {given_name_initial} {surname}, which has resulted in me getting mis-delivered mail from people all over the world.

If the message is from a real person, I'll reply "hey, you got the wrong guy" (I've been on work email chains, gotten party invites, etc). But sometimes the comes from an automated source that I don't know how to reply but seems pretty important (e.g., purchase receipts, bank summary statements, insurance benefits info).

Obviously, this wouldn't be a problem if organizations did email proper email verification before sending important messages, but they are not. I'd like to stop this annoying pseudo-spam for me, and I'm sure other people would like to get their important missing messages.

A few things that I've tried:

A few times, these mis-delivered messages have provided me a postal address, so I've been able to send an actual letter saying "FYI, you or your bank is using the wrong email. You should probably try to fix that".

Other times, I've tried sending a reply to support addresses, but that usually ends up in a kafka-esque nightmare of explaining that the account for userid "name@gmail.com" should not use the email "name@gmail.com".

So... what's the neighborly good-citizen approach to fixing this?