@blog As an old IT geek that started in this game long before the modern internet (I had an email address in the 1980s when all it could do was talk to UK or US universities or the military via JANET or DARPANET etc.over UUCP) I have been increasingly depressed at how big US tech has worked so hard at killing off the original,, open, standardised, federrated design principles of the web and sucking everyone into their closed silos.
Email is one of the original protocols in use and is still federated in theory but nearly everyone iis forced onto Google or Microsoft as there are few good alternatives.
I have hosted own email (plus calendar and contacts) for 25 years now. Not too tricky if you are IT savvy... but...
My stack (all open source):
Opensuse Linux
Postfix email server
MariaDB database
Dovecot IMAP server
Apache web server
Amavis anti-spam/anti-virus
Spamassasin spam filters
SOGo groupware
Plus good secure DNS with SPF, DKIM and DMARC records and reverse-ip for the server.
Give it a go!