I use Radicale for my calendars and contacts as basically every program, app or device can handle caldav/carddav.

Self-hosting email however is too painful. Not that it isn’t easy on principle… but because the basics are simple all the big mail providers have developed a lot of ways to automatically filter out all those quickly put up mail servers mainly used to distribute spam. So having your own mail server while also constantly jumping through all the hoops so your mails are actually received is barely worth it.