Server-wise you want either ejabberd or prosody for the latest features. Yes, you need to set up a server once and read some docs, as with every self-hosted service. And if you don't care about encryption enough to read about it you can just enforce TLS for client-to-server and server-to-server connections. On the desktop, Gajim (win/linux/bsd/mac) supports all of the XEPs I mentioned. There are clients for iOS too but I don't know how they work as I don't own any Apple products.

Of course, if you'd rather spend money than time hoping that your provider won't have your conversations stolen, misused or disappear with them that's your prerogative too.