Because there’s sales text in the “educational” article.
You should use an XMPP server that respects your privacy. If you truly want privacy and don’t want to trust any server, we recommend setting up your own server. If this beyond your technical interests then we can setup a server for you and hand over the passwords. If we setup a server for you, then you’d pick the domain name and get complete control over who can use it.
It’s an extinct volcano, so yes.