> (replacement for Mailchimp)
Gmail and friends have successfully re-centralised email (in the name of spam control). So bulk emailing will also be inherently centralised, thus the very limited choices. substack will, at some point, either stand strong--and be blacklisted by the email monopolists. Or fold, and there you are. Again.
The Fediverse would work, but it push based, so spam can be a problem. RSS is pull, thus hard to spam.
This is a family server