I’ve used email a bit and there are some pros and cons. For email: It’s just there already, like you mention. Once you are setup you can do things like comment

I’ve used email a bit and there are some pros and cons. For email: It’s just there already, like you mention. Once you are setup you can do things like comment on a “line of code” very straightforwardly. It’s already distributed and all that. There are bespoke (project-specific probably) bridges from forges (maybe mostly GitHub) to mailing lists. For this new thing: You don’t have to worry about all the legacy of email. You don’t have to worry about 90% of the world using email “wrong” according to techies. You can probably track changes more easily than keeping track of where you sent patches. You don’t have to make bespoke forge-to-email bridges.