I still don't understand why, for projects and similar topics-based discussion, we don't use NNTP instead of Email. Email is good for addressing specific people only, and you're supposed to have been part of the conversation since the beginning so it does apply to personal correspondence but it scales horribly bad for groups of people:

- there is no included history. You need to manually download hand-crafted archives from a bespoke endpoint but then you need to import it all. If you want to quickly read some old message there needs to be a relay to a public inbox type of thing which is a hack

- mailing lists software exist but they are another hack. There is no standard for subscribing or unsubscribing

- projects often have multiple lists anyway so they need to install them all

All of these issues are solved with a network of NNTP servers, and even more: automatic backup of posts because that's how NNTP works, messages are shared accross the network so every message has a specific URI (https://tools.ietf.org/html/rfc5538) and can be addressed directly and retrieved on-the-fly if needed