If your mail server supports #sieve scripts, you can use that for a very basic mailing list. It's absolutely not capable of much more than the original reflector concept, but it has served me well, so it's in my GoodEnoughâ„¢ bucket :) Maybe you want to play with this too? Not everyone wants to learn how to install and run mailman, but everyone should be able to run their own mailing lists in these weird times ;)
https://codeberg.org/jwildeboer/gists/src/branch/main/2023/20230305SieveML.md


